In/ 


■W!S.I.,ARD  ^,IJ3LV'IlD 


ID] 


:VTL 


1 


A 


•JJ 
/6 


Digitized  by  the  Internet  Archive 

in  2007  with  funding  from 

Microsoft  Corporation 


http://www.archive.org/details/fernalliesofnortOOclutrich 


THE  FERN  ALLIES 


P L AT E  S\  iOCyijl  M i)N'  \StJo;U  R^  N/i- R U I H .     Eqiiisetiim 

•••••*•  c'    «    *c»         fc    t  tti   c'**c    *c* 


Jiietnale. 


CCPYRIOH 


1,   1905,    BY    f  HELERICK    A.   STOKES  COMrA^ 


THE  FERN  ALLIES 

OF 

TFlortb  Hmerica  IRortb  ot  /IDejico 

BY 
WILLARD  NELSON  CLUTE 

Author  of  '"''  A  Flora  of  the  Upper  Susqneha/ina,''^  ''  The  Fern 
Collector  s  Guide '^  "  Our  Ferns  in  their  Haunts,^''  etc. 


WITH  MORE  THAN  ONE  HUNDRED  AND  FIFTY 
ILLUSTRATIONS  BY 

IDA  MARTIN  CLUTE 


;*, 


NEW  YORK 

FREDERICK  A.  STOKES  COMPANY 

PUBLISHERS 


Copyright,  1905, 
By  Frederick  A.  Stokes  Company. 


This  edition  published  in  September,  1905. 


^^°^ 


»RN«^ 


CONTENTS. 


PAGE 


List  of  Illustrations  .        .        .        .        .    vii 

Preface .        .     xi 

The  Fern  Allies    .        . i 

Key  to  the  Families  of  Fern  Allies      .        .      8 
The      EQUiSETACE^i:     Scouring-Rushes     and 

Horsetails 9 

Key  to  the  Species  of  Equisetum    .        .        .16 
The    Evergreen    Equisetums,   or    Scouring- 
Rushes    .        .        .        ,        .        .        .        .     \j 
The  Deciduous  Equisetums,  or  Horsetails    .    41 
The  Lycopodiace^:,  or  Club-Mosses  .        .        .69 

Key  to  the  Lycopodiums jj 

The  Trailing  Lycopodiums  .        .        .        .79 

The  Erect  or  Decumbent  Lycopodiums  .        .  105 

The  Psilotace^ .123 

The  Selaginellace^,  or  Dwarf  Club-Mosses  129 

Key  to  the  Selaginellas 135 

The  True  Selaginellas,  or  Selaginella   Ru- 

PESTRis  Group 137 

The  Creeping  Selaginella  Group     .        .        .153 

The  SALViNiACEyii 167 

Salvinia .173 

The  Azollas 179 

The  Marsiliace^:,  or  Pepperworts  .        .        .185 

Key  to  the  Marsilias 191 

The  Marsilias         ...,.,.  193 


298644 


vi 


CONTENTS. 


The  Isoetace^,  or  Quillworts 
Key  to  the  Isoetes 
The  Aquatic  Quillworts    . 
The  Amphibious  Quillworts 
The  Terrestrial  Quillworts 
Checklist  of  the  Fern  Allies 
Glossary  .... 

Index  to  the  Common   Names 
Index  to  the  Scientific  Names 


207 
216 
217 
231 
247 

255 
267 

274 
276 


List   of  Illustrations, 


COMMON  SCOURING-RUSH.     Equisetuin  hieinale.     (In  colours.)    .  Frontispiece. 

PAGE 

SECTION  OF  SCOURING-RUSH  STEM             ........  12 

JOINT  OF  SCOURING-RUSH  STEM 13 

SPORE-CASES              13 

SPORES,  ENLARGED 14 

CROSS  SECTION  OF  STEM  OF  COMMON  SCOURING-RUSH       ....  19 

YOUNG  STEMS  OF  COMMON  SCOURING  RUSH 20 

FERTILE  STEM  OF  COMMON  SCOURING  RUSH.     Equisetum  hieninle             .  22 

SHEATH  OF  GREAT  SCOURING-RUSH.       Equisetuin  robusium         ...  26 

EQUISETUM  FERRISSI,  SECTION  OF  STEM 28 

EQUISETUM  FERRISSI,  TIP  OF  STEM 3° 

SMOOTH  SCOURING-RUSH.      Equisetum  la-vigntum          ....        facing  30 

SHEATH  OF  SMOOTH  SCOURING-RUSH 32 

CATKIN  OF  SMOOTH  SCOURING-RUSH 32 

BRANCHED  EQUISETUM.      Equisetuin  Eunstoni facing  34 

SHEATH  OF  EQUISETUM   FUNSTONI 34 

CATKIN  OF  EQUISETUM   FUNSTONI        •          •         - 35 

SHEATH  OF  VARIEGATED  SCOURING-RUSH 36 

VARIEGATED  SCOURING   RUSH.     Equisetuin  variegatum        ,         .         .         facing  36 

CATKIN  OF  VARIEGATED   SCOURING-RUSH. 37 

SECTION  OF  VARIEGATED  SCOURING-RUSH  STEM 38 

DWARF  SCOURING-RUSH.      Equisetum  scirpoides facing  38 

SHEATH  OF  DWARF  SCOURING-RUSH           ........  39 

CATKIN  OF  DWARF  SCOURING-RUSH 40 

STERILE  FROND  OF  FIELD  HORSETAIL.     Equisetuin  arvense          .         .        facing  44 

FERTILE  FROND  OF  FIELD  HORSETAIL facing  44 

SECTION  OF  FIELD  HORSETAIL  STEM 46 

WOOD  HORSETAIL.     Equisetuin  silvatictim.    (In  colours)         .         .         .       facing  46 

EQUISETUM  ARVENSE  DECUMBENS facing  48 

EQUISETUM  ARVENSE   CAMPESTRE facing  48 

BUDS  AND  TUBERS  OF  FIELD  HORSETAIL '         •  49 

FERTILE  FROND  OF  IVORY  HORSETAIL,     Equisetum  telmateia       .         .        facing  50 

SECTION  OF  STERILE  FROND  OF  IVORY  HORSETAIL        ....       facing  52 

STERILE  FROND  OF  SHADE  HORSETAIL.     Equisetum pratense       .         .        facing  54 

FERTILE  FROND  OF  SHADE   HORSETAIL facing  54 

STERILE  FROND  OFWOOD  HORSETAIL.     Equisetuin   silvaticunt           .        facing  56 

FERTILE  FROND  OF  WOOD  HORSETAIL facing  56 

BUDS  AND  TUBERS  OF  WOOD  HORSETAIL 57 


VIU 


LIST  OF  ILLUSTRATIONS. 


PA 

WATER  HORSETAIL.     Egniseium  fluviatile /ndng 

WATER  HORSETAIL.     Jiquisetuiu  Jluviatilc.    (In  colours)         .         .         .       facing 

SECTION  OF  WATER  HORSETAIL  STEM 

MARSH  HORSETAIL.      JCqui^etuiii  />auisire facing 

A  FORM  OF  EQUISETUM  LITTORALE facing 

FORMS  OF  SHORE  HORSETAIL facing 

A  MOSS  CAPSULE , 

FRUITING-SPIKE  OFLYCOPODIUM 

SPOROPHYLL  OF  LVCOPODIUM 

SPOROPHYLLS  OF  VARIOUS  LYCOPODIUMS  

COMMON  CLUB-MOSS.     Lycopodiuiii  claiuituin facing 

LYCOPODIUM  CLAVATUM  MONOSTACHYON       •  

STIFF  CLUB-MOSS.     Lycopodinin  nnnotinuin facing 

LYCOPODIUM  ANNOTINUM  PUNGENS facing 

BRANCHLET  OF  LYCOPODIUM  COMPLANATUM 

GROUND-PINE.     Lycopodinin  contplanatuiii facing 

BRANCHLET  OF  LYCOPODIUM  COMPLANATUM  CHAM/ECYPARISSUS  • 
LYCOPODIUM  COMPLANATUM  CHAM/ECYPARISSUS  ....        facing 

GROUNDFIR.     Lycopodinin  alpinurn facing 

BRANCH  OF  LYCOPODIUM  ALPINUM 

SAVIN-LEAVED  CLUBMOSS.     Lycopodinni  sabincefolium  .         .         .        facing 

BRANCH  OF  LYCOPODIUM  SABIN/EFOLIUM  ...  ... 

LYCOPODIUM  SITCHENSE facing 

BRANCH  OF  LYCOPODIUM  SITGHENSE 

TREE  CLUBMOSS.     L.ycopodium  ohscuruni.    (In  colours)         .         .         .        facing 

TREE  CLUB-MOSS.     Lycopodiujn  odscuruin facing 

STAG-HORN  CLUB-MOSS.     I^ycopodiuni  cernuuni facing 

SHINING  CLUB-MOSS.     Lycopodinin  lucidulunt facing 

SPORANGIA  OF  SHINING  CLUB-MOSS 

LYCOPODIUM  LUCIDULUM  POROPHILUM f^icing 

BULBLET  OF  SHINING  CLUBMOSS 

FIR  CLUB-MOSS.     Lycopodinin  selago facing 

BOG  CLUB-MOSS.    Lycopodinin  inundatuin facing 

FOX-TAIL  CLUB-MOSS.     Lycopodinin  alopccnroidcs  ....        facing 

LYCOPODIUM  ALOPECUROIDES  ADPRESSUM      ......        facing 

LYCOPODIUM    ALOPECUROIDES  ADPRESSUM.     (In  colours)    .         .         .        facing 
CAROLINA  CLUB-MOSS.     LyCopodium  Carolinianuin        ....        facing 

SYNANGIA  OF  PSILOTUM 

PSILOTUM  TRIQUETRUM facing 

MEGASPORE  OF  SELAGINELLA  RUPESTRIS 

ROCK  SELAGINELLA       Sclagincila  rnpe^tris.     (In  colours)       .         .         .        facing 

SPIKE  OF  SELAGINELLA 

LEAF  OF  SELAGINELLA  RUPESTRIS  

LEAVES  OF  A  BIMORPHIC  SELAGINELLA 

ROCK  SELAGINELLA.    Sciaginclia  rupcstris facing 

SPIKE  OF  ROCK  SELAGINELLA 

BRANCH  OF  SELAGINELLA  WATSONI     .  •  •  

SAND  BARREN  SELAGINELLA.    '*>>^".*r'«''^/« 'i^*""'"'"^'*          •         •         •         •,       • 
SELAGINELLA  BIGELOVII '         •        /"""A' 


GE. 

58 
60 
61 
62 
64 
66 
71 
73 
73 
74 
82 
84 


LIST  OF  ILLUSTRATIONS. 


SELAGINELLA  CINERASCENS  .... 

OREGON  SELAGINELLA.     Selaghiella  Oregnna 
PRICKLY  MOUNTAIN  MOSS.     Selaginella  sfiinosa 
CREEPING  SELAGINELLA.    Selaginella  afius 
SPIKE  OF  CREEPING  SELAGINELLA       • 
SELAGINELLA  LUDOVICIANA  .... 

SELAGINELLA  LUDOVICIANA.      (I"  colours) 
SELAGINELLA  DOUGLASII         •         •         •  "      • 
RESURRECTION  MOSS.     Selaginella  !c/>ido/>hyna 
BRANCH  OF  THE  RESURRECTION  MOSS       • 
RESURRECTION  MOSS,  WHEN  DRY 

SPOROCARPS  OF  AZOLLA 

SALVINIA  NATANS 

CROSS-SECTION  OF  SALVINIA  SPOROCARPS 
SPOROCARPS  OF  SALVINIA  NATANS      • 
WATER  FERN.     Azolla  Caroliniaita 

THE  HOME  OF  AZOLLA 

AZOLLA  FILICULOIDES     •..••• 
SPOROCARP  AND  SPORANGIA  OF  MARSILIA 
VEINING  IN  THE  LEAF  OFMARSILIA       • 

SPOROCARP  OF  MARSILIA 

CROSS-SECTION  OF  PILULARIA  SPOROCARP      • 
MARSILIA  QUADRIFOLIA.     (In  colours) 
MARSILIA  QUADRIFOLIA 


MARSILIA  UNCINATA 

MARSILIA  VESTITA    • 

MARSILIA  MACROPODA 

PILULARIA  AMERICANA 

LEAF  OF  ISOETES  SHOWING  SPORANGIUM 

CROSS-SECTION  OF  ISOETES  LEAF       .... 

MEGASPORES  OF  ISOETES 

MICROSPORES  OF  ISOETES 

BRAUN'S   QUILLWORT.     Isoetes  echinosporn  Brnunii 

MEGASPORE  OF  BRAUNS  QUILLWORT 

MEGASPORE  OF  ISOETES  ECHINOSPORA  MURICATA 

MEGASPORE  OF  ISOETES  TRUNCATA 

MEGASPORE  OF  ISOETES  ECHINOSPORA  FLETTII    • 

MEGASPORE  OF  ISOETES  LACUSTRIS 

MEGASPORE  OF  TUCKERMAN'S    QUILLWORT.      Isoetes  Titckc 

MEGASPORE  OF  BOLANDER'S  QUILLWORT.    Jsoetes  Bolandc. 

MEGASPORE  OF  ISOETES  HIEROGLYPHICA 

MEGASPORE  OF  ISOETES  MACOUNI      .... 

ENGELMANN'S  QUILLWORT.     Isoetes  Engebiinnni     . 

MEGASPORE  OF  ENGELMANN'S  QUILLWORT      • 

MEGASPORE  OF  ISOETES  ENGELMANNI  CAROLINIANA 

MEGASPORE  OF  EATON'S  QUILLWORT.    Lwetes  vnlida 

MEGASPORE  OF  DODGE'S  QUILLWORT.     Isoetes  Canndensi 

MEGASPORE  OF  RIVER-BANK  QUILLWORT.    Isoetes  ripatiu 

MEGASPORE  OF  ISOETES  SACCHARATA     .... 


facing 
facing 
facing 


facing 
facing 

facing 

facing 


GE. 

146 

143 

150 

156 


160 

160 

162 
162 

164 

171 

176 

171 

176 


facing 


213 
214 
220 
220 
221 
222 
222 
224 
225 


22g 
229 
facing  234 
234 
235 
236 
238 
239 
24c 


facing 
facing 
facing 
facing 
facing 
facing 


facing 


LIST  OF  ILLUSTRATIONS. 


r/EGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 
MEGASPORE 


OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 
OF  ISOETES 


FOVEOLATA 
GRAVESII  • 
MELANOSPORA 
FLACCIDA  • 
HOWELLI  • 
MELANOPODA 
BUTLERI  • 
NUTTALLII  • 
ORCUTTI  • 
MINIMA 


I'AGE. 

241 
243 
244 
244 
246 
251 
252 
253 
253 
254 


PREFACE 

The  Fern  Allies,  by  reason  of  their  curious  forms  and 
often  great  abundance,  seldom  fail  to  attract  the  atten 
tion  of  the  student  of  plants,  but  their  identification  has 
always  proved  more  or  less  of  a  puzzle  to  beginners. 
Like  the  ferns,  they  bear  neither  flowers  nor  seeds,  and 
at  first  glance  seem  to  offer  few  points  by  which  they 
may  be  distinguished.  The  species  are  usually  included 
in  botanical  Manuals,  but  the  necessarily  brief  and  tech- 
nical descriptions  have  tended  to  discourage  rather  than 
to  aid  the  novice.  In  reality,  however,  most  of  the 
species  are  easily  identified,  and  it  is  one  of  the  purposes 
of  this  book  to  point  out  how  this  may  be  done. 

No  book  has  ever  before  been  published  in  which  one 
may  find  untechnical  descriptions  of  our  fern  allies,  nor 
one  in  which  all  the  species  have  been  figured  ;  in  fact  a 
large  number  are  figured  for  the  first  time  in  this  book. 
Such  illustrations  as  have  hitherto  appeared  are  scattered 
in  various  American  and  foreign  books,  often  inaccessi- 
ble, many  of  which,  published  long  ago,  are  more  or  less 
inaccurate.  It  has  been  our  aim,  not  only  to  illustrate 
every  species,  but  to  represent  them  correctly.  The 
drawings  have  been  made  from  typical  specimens  of  the 
plants,  and  it  is  believed  that  many  of  the  species  will 
now  be  easily  identified  by  merely  comparing  them  with 
the  illustrations. 

In  the  text  each  species  has  been  carefully  described 
anew  from  authentic  specimens,  and  all  the  known  facts 


xii  PREFACE. 

in  its  life  history  added.  Preceding  the  acconnt  of  the 
species  in  each  genns  will  be  found  a  chapter  on  the 
group  as  a  whole,  followed  by  a  Key  to  the  species.  In 
each  group  of  species  the  best  known  is  placed  first,  and 
those  that  follow  are  frequently  compared  with  it. 
Many  of  these  plants  have  received  so  little  study  from 
botanists  that  scarcely  anything  is  known  about  them. 
In  a  further  study  of  the  life  histories  of  these  species  the 
beginner  will  find  a  new  and  inviting  field  in  which  he 
will  be  a  discoverer  rather  than  a  gleaner.  I  shall  be 
glad  to  receive  notes  of  this  kind,  and  offer  to  identity 
any  species  that  may  prove  troublesome,  provided  good 
herbarium  specimens  are  sent  me,  accompanied  by  post- 
age for  reply.  I  cannot  undertake  to  return  such  speci- 
mens, however. 

Among  technical  works  relating  to  the  American 
species,  first  place  must  be  given  to  Underwood's  "  Our 
Native  Ferns  and  Their  Allies,"  which  includes  brief 
descriptions'  of  all  but  the  most  recently  discovered 
species  in  North  America  north  of  Mexico.  Dodge's 
"  Ferns  and  Fern  Allies  of  New  England "  contains 
somewhat  more  extended  accounts  of  the  New  England 
species,  with  an  excellent  chapter  on  the  identification 
of  Isoetes  and  a  list  of  the  species  arranged  according  to 
the  time  each  fruits.  Eastman's  "  New  England  Ferns 
and  Their  Common  Allies,"  in  which  there  are  illustra- 
tions and  untechnical  descriptions  of  a  few  of  the  com- 
mon species,  completes  the  list  of  works  devoted  exclu- 
sively to  the  subject.  Of  foreign  works.  Baker's  "  Hand- 
book of  the  Fern  Allies,"  published  in  1887,  includes 
short  descriptions  of  all  the  species  in  the  world  that 
were  known  at  the  time  of  publication.  Some  mention 
should  also  be  made  of  "  T/ie  Fern  Bulletin''  now  in  its 


PREFACE.  xiii 

thirteenth  volume,  which  enjoys  the  unique  distinction 
of  being  the  only  publication  in  the  world  devoted  to 
the  ferns  and  fern  allies.  In  past  volumes  it  has 
published  much  regarding  the  haunts  and  habits  of  the 
plants,  including  descriptions  of  many  new  species  and 
forms.  A  series  of  Fern  Floras  of  the  States  is  now 
being  published,  which  gives  lists  of  the  ferns  and  fern 
allies  in  each  State,  with  distribution  and  other  notes 
added. 

In  the  matter  of  nomenclature  Ihave  adopted  a  some- 
what conservative  treatment,  preferring  for  the  most  part 
the  names  commonly  used,  since  these  will  be  most  fre- 
quently found  in  other  books.  When  they  differ  from 
others  recently  proposed,  the  latter  are  given  also,  and 
they  have  also  been  included  in  the  Checklist  of  the 
species.  It  does  not  seem  advisable,  in  a  work  of  this 
kind,  to  follow  the  practice  of  radical  botanists  in  treat- 
ing a  large  number  of  forms  as  species.  It  is  possible 
that  some  of  these  forms  may  be  found  to  have  characters 
of  specific  importance,  but  it  will  be  less  confusing  to 
the  beginner  if  they  are  still  regarded  as  forms  of  the 
species  from  which  they  have  been  segregated. 

These  newly  named  forms  have  had  to  be  recognized, 
however,  and  in  giving  them  what  I  believe  to  be  their 
rightful  places  a  aumber  of  new  combinations  have  un- 
avoidably been  made.  In  no  other  way  has  it  seemed 
possible  to  indicate  to  beginners  the  various  disguises 
under  which  certain  plants  are  likely  to  be  found  in  com- 
ing years.  In  the  Checklist  I  have  followed  the  plan 
of  citing  the  authority  for  the  species  only,  believing 
that  the  author  of  a  new  combination  is  not  entitled  to 
the  prominence  which  a  double  citation  of  authorities 
confers. 


xiv  PREFACE. 

Much  valuable  assistance  in  the  preparation  of  this 
book  has  been  given  me  by  students  of  the  fern  allies. 
The  source  of  many  notes  has'been  indicated  in  the  text, 
but  I  am  especially  indebted  to,  and  wish  here  to  thank, 
Mr.  S.  B.  Parish,  Mr.  A.  J.  Hill,  Mr.  C.  H.  Demetrio, 
Dr.  C.  B.  Graves,  Mr.  J.  B.  Flett,  Mr.  Julian  Reverchon, 
Prof.  R.  S.  Cocks,  Mr.  Thomas  Howell,  Mr.  M.  L. 
Fernald,  Mr.  J.  H.  Ferriss,  Miss  E.  Cannon,  and  Miss  L. 
F.  Kimball.  Mr.  Alvah  A.  Eaton,  of  the  Ames  Botani- 
cal Laboratory,  whose  studies  of  these  plants  have  con- 
tributed so  much  to  our  knowledge,  has  rendered 
invaluable  assistance  by  the  loan  of  specimens,  by  send- 
ing many  interesting  notes,  and  by  a  critical  reading  of 
the  proof.  It  is  but  fair  to  add,  however,  that  in  matters 
of  nomenclature  and  the  limitations  of  species  I  have 
not  always  followed  his  suggestions. 

WiLLARD    N.   ClUTE. 

Joliet,  111., 

February  27,  1905. 


THE  FERN  ALLIES 


J     J      J    '    9   '     i      , 


^ 


THE  FERN  ALLIES, 


INCE    ferns  are   members    of 
the  vegetable  kingdom,  all 
plants    are    more    or    less 
allied  to  them,  but  the  term  Fern  Allies, 
as    commonly    understood,   has    a    much 
more  restricted    meaning.     As  regarded 
by  botanists,  the  fern   allies    are    plants 
belonging  to  certain  families  included  in 
one  of    the  great  natural  groups  of   the 
flowerless    plants.      The  fern    allies   are 
quite  unlike  flowering  plants  in  appear- 
ance and  have  little  more  resemblance  to 
their  allies,  the  ferns  ;  but  their  structure 
and    manner    of    fruiting    show 
them  to  be  closely  related. 

Botanists  long  ago  divided  the 
vegetable  kingdom  into  two 
sub-kingdoms  which  they  nam.ed 
respectively  the  Phancrogamia, 
or  Flowering  Plants,  and  the 
Cryptogaviia,  or  Flowerless 
Plants.     In  this  second  division 


4  THE  FERN  ALLIES. 

were  placed  such  diverse  plants  as  the  algae,  fungi,  liver- 
worts, mosses,  and  ferns.  None  of  these  ever  bear 
flowers  or  produce  seeds,  but,  aside  from  this,  the 
various  groups  differ  as  much  among  themselves  as  the 
division  as  a  whole  differs  from  the  flowering  plants. 
The  ferns  and  fern  allies  are  the  most  highly  developed 
of  these  plant  families,  and  in  structure  are  closely  re- 
lated to  the  simplest  flowering  plants.  They,  alone,  have 
true  roots  and  stems  with  tissues  specialized  for  different 
functions.  The  presence  of  these  specialized  tissues  — 
the  so-called  fibro-vascular  system  —  has  caused  these 
plants  to  be  called  Vascular  Cryptogams  or  Vascu- 
lar Acrogens  to  distinguish  them  from  the  less-spe- 
cialized mosses,  algae,  etc.,  composing  the  Cellular 
Acrogens. 

Modern  botany  still  accepts  these  divisions,  though 
the  terms  used  to  designate  them  have  changed  some- 
what as  they  have  become  adjusted  to  our  present 
ideas  of  nomenclature.  We  now  usually  speak  of  flower- 
ing plants  as  the  Spcnnatophyta,  and  of  the  ferns  and 
fern-like  plants  (the  vascular  acrogens)  as  the  Pterido- 
pJiyta.  The  mosses  and  liverworts  are  now  the  BryopJiyta^ 
and  the  rest  of  the  cellular  acrogens  are  spoken  of  as  the 
TJiallophyta.  The  fern  allies,  then,  belong  to  the  high- 
est division  of  the  flowerless  plants,  have  stems  in 
which  there  are  woody  tissues  and  ducts,  and,  in 
short,  comprise  all  the  PtcridopJiyta  except  the 
ferns  themselves,  as  shown  by  the  accompanying 
table  of  the  orders  represented  in  the  North  Ameri- 
can Flora. 


THE  FERN  ALLIES.  5 

ORDERS     AND     FAMILIES     OF     THE     NORTH     AMERICAN 
PTERIDOPHYTA. 

SERIES  I. —FERNS. 

Order  i.  —  Ophioglossales. 

Family   i. —  Ophioglossacece. 
Order  2.  — P^ilicales. 

Family  i . — Hymejiophyllacece, 

Family  2. — Osmimdacece. 

Family  3. — SchisceacecB. 

Fainily  4. — Ceratopteridacece. 

Fa  m  ily  5 .  — Polypodia  cece, 

SERIES  II. —  FERN  ALLIES. 

Order  i.  — Salviniales. 

Family  i . — Marsiliacece, 

Family  2. — Salviniacecs. 
Order  2.  —  Equisetales. 

Family  i. — EquisetacecB, 
Order  3.  —  Lycopodiales. 

Family  i. — Lycopodiacece. 

Family  2. — Psilotacece. 

Family  3. — Selagiiiellacece, 
Order  4.  —  Isoetales. 

Fa  m  ily  i .  — Isoeta  cecB. 

Like  the  ferns,  the  fern  alHes  are  reproduced  by  spores, 
which,  germinating^,  form  prothallia  upon  which  the 
reproductive  organs,  the  antheridia  and  archegonia,  are 
borne.  From  the  union  of  the  contents  of  archegonia 
and  antheridia,  new  plants  are  produced.  The  pro- 
thallia, however,  are  often  quite  unlike  the  familiar 
green,  heart-shaped  prothallia  of  the  fern.  Some  are 
colourless,  tuber-like,  and  develop  underground  instead  of 
upon  the  surface  in  the  usual  way,  and  in  some  that 
develop  above  ground  the  prothallia  are  not  heart- 
shaped  and  the  antheridia  and  archegonia  are  on  sepa- 
rate prothallia.    The  process  of  fertilization  is  essentially 


6  THE  FERN  ALLIES. 

the  same  in  all,  —  a  fusing  of  the  contents  of  archegonia 
and  antheridia. 

The  ferns  are  a  strongly  marked  and  easily  recognized 
group  of  plants,  but  the  fern  allies  have  no  such 
uniformity  of  appearance.  Only  the  botanist,  familiar 
with  their  manner  of  fruiting,  would  think  of  associating 
plants  of  such  diverse  habits  and  dissimilar  forms.  The 
club-mosses  usually  have  trailing  vine-like  stems  and 
tiny  scale-like  leaves  ;  the  selaginellas  grow  in  moss-like 
tufts;  the  pepperworts  have  leaves  resembling  four- 
leaved  clovers  ;  the  quillworts  have  very  short  trunks 
and  grass-like  leaves  ;  while  the  scouring-rushes,  at  first 
glance,  seem  to  have  no  leaves  at  all  and  to  be  chiefly 
remarkable  for  their  development  of  stem.  Neverthe- 
less, all  are  practically  alike  in  their  manner  of  fruiting 
and  in  the  structure  of  the  plant  body,  and  are  therefore 
properly  classed  together. 

The  great  diversity  of  leaf  and  stem  in  the  fern  allies 
is  made  necessary  by  the  habitats  of  the  plants.  The 
club-mosses  live  on  dry  moors,  in  rocky  wastes,  or 
sandy  swamps ;  the  scouring-rushes  in  damp  shades  or 
standing  water.  The  water-fern  is  found  floating  on  the 
surface  of-  quiet  pools;  the  marsilias  root  beneath  the 
water  and  send  their  leaves  to  the  surface  ;  while  many 
of  the  quillworts  pass  their  entire  life  at  the  bottom  of 
rivers,  lakes,  and  ponds. 

As  a  whole,  the  fern  allies  are  members  of  a  decadent 
group,  and  the  lack  of  close  resemblances  between  the 
families  is  doubtless  to  be  explained  upon  the  supposi- 
tion that  many  of  the  intergrading  forms  have  died  out. 
At  present  there  are  about  seven  hundred  living  species, 
or  approximately  one  for  every  six  species  of  ferns.  In 
the  remote  past  they  were  much   greater  in  both  num- 


THE  FERN  ALLIES.  7 

bers  and  importance.  The  prototypes  of  our  lowly 
club-mosses  and  scourlng-rushes  —  the  lepidodendrons, 
sigiilarias,  and  calamites  —  often  equalled  in  size  the 
forest  trees  of  the  present,  and  their  remains  form  the 
greater  part  of  the  Coal  Measures.  It  is  reported  that 
one  of  the  Scottish  coal  beds  consists  almost  entirely  of 
the  spores  and  spore-cases  of  some  extinct  Lycopoditini. 
Of  our  modern  genera,  Equisetiiin  dates  from  the 
Triassic  Period ;  Isoctes,  Marsiiia^  and  Pihilaria  from 
the  Tertiary  ;  and  Lycopodium  from  as  far  back  as  the 
Devonian  Period. 

With  few  exceptions  the  fern  allies  are  not  remark- 
able for  either  beauty  or  utility.  Some  of  the  club- 
mosses,  under  the  more  familiar  names  of  running  pine 
and  trailing  evergreen,  are  annually  used  in  quantity  for 
holiday  decorations,  and  various  species  of  Selaginella 
are  cultivated  for  their  graceful  foliage.  The  spores  of 
the  club-mosses  form  the  lycopodium  of  the  pharmacist 
and  have  been  used  in  the  manufacture  of  fireworks, 
while  the  rough  stems  of  the  scou ring-rushes  were  once 
valued  for  polishing  and  scouring. 


Key  to  the  Families  of  the  Fern  Allies. 


I.  —  Sporangia  in  terminal  cones 

Stems  hollow,  rush-like  .  .     Equisetacece 

11.  — Sporangia  in  the  axils  of  the  leaves  or  leaf- 
like  bracts,  often  forming  terminal 
spikes 
Plants  apparently  stem  less       .  .  IsoetacecB 

Plants  with  evident  stems 

Spores  of  two  sizes  .  SelaginellacecB 

Spores  all  alike 

Sporangia  in  spikes    .  Lycopodiacece 

Sporangia  in  clusters  .        PsilotacecB 

III.  —  Sporangia  in  berry-like  sporocarps 

Whole  plant  floating    .  .  .     SalviniacecE 

Plant  rooting  in  mud    .  .  .    Marst'h'accce 


» 


THE  EQUISETACE^: 
SCOURING-RUSHES  AND  HORSETAILS. 


THE  EQUISETACE^. 


OT  inappropriately  may  the  Scoiir- 
ing-Rushes  be  likened  to  the 
cacti,  for,  like  them,  their  leaves 
are  reduced  to  mere  rudiments, 
and  the  stems  perform  all  the 
ofifices  usual  to  leaves.  This, 
however,  is  not  their  only 
peculiarity.  In  their  general 
structure  they  have  little  re- 
semblance to  other  plants.  The  stems  are  jointed,  hollow 
except  at  the  joints,  and  noticeable  for  their  lack  of 
differentiation  from  the  underground  portion  of  the 
plant.  From  the  farthest  subterranean  root-stock  to  the 
tip  of  the  tallest  shoot,  the  construction  is  essentially 
the  same.  It  may  be  likened  to  a  line  of  drain-pipe,  each 
section  of  which  fits  Into  the  slightly  flaring  top  of  the 
one  below  it.  These  hollow  sections  are  grooved  exte- 
riorly with  from  three  to  fifty  longitudinal  grooves,  vary- 
ing in  number  with  the  species.  These  grooves  are 
known  as  valleculas  and  the  intervening  ridges  as  carinae. 
Within  the  stem  walls,  and  encircling  the  central  hollow, 
there  are  usually  found  two  other  series  of  hollows, — 
one  series  beneath  the  valleculae,  and  therefore  called  the 
vallecular  canals  ;  the  other  beneath  the  carlnae,  and  called 


12  THE  EQUiSETACE/E. 

the  carinal  canals.  These  differ  in  size  and  shape  with 
the  species,  and  thus  form  excellent  characters  for  their 
identification. 

At  the  top  of  each  joint  in  the  stem  there  is  a 
papery  sheath  which  seems  to  form  a  socket 
into  which  the  next  joint  above  it  fits.  This 
sheath  is  toothed  on  its  upper  border,  usually 
with  as  many  teeth  as  there  are  ridges  in  the 
stem.  From  various  indications  it  is  evident 
that  this  sheath  represents  a  circle  of  confluent 
but  reduced  and  functionally  useless  leaves. 
Inside  the  sheath  (that  is,  in  the  axils  of  the 
leaves)  buds  are  formed, —  a  bud  for  each  leaf,  — 
and  if  these  develop  into  branches  they  break 
out  throusrh  the  base  of  the  sheath  in  reg-ular 
whorls.  In  many  species  these  buds  always 
remain   dormant   unless    the  tip  of  the  stem  is    Section  of 

.     .  .  Stem  at 

injured,  when  a  few  near  the  tip  may  give  rise  the  sheath. 
to  short  branches. 

Externally  the  stems  are  often  coated  with  particles 
of  silex  in  many  curious  patterns,  such  as  rings,  bands, 
granules,  teeth,  and  rosettes;  and,  not  infrequently, 
abundant  silex  particles  may  be  found  lining  the  central 
hollow.  This  silicious  coating  gives  a  characteristic 
harshness  to  the  stems  of  certain  species,  rendering 
them  useful  for  polishing  woodwork  and  other  articles. 
The  silex  is  usually  most  abundant  on  the  carinae,  while 
the  stomata — the  minute  openings  for  transpiration  — 
are  distributed  along  the  valleculae. 

The  rhizome  or  underground  portion  of  the  plant  is 
often  of  considerable  length,  and  spreads  about  in  the 
earth  from  a  few  inches  to  several  feet  beneath  the  Sur- 
face.    The   sheaths  at  the  joints  also  contain  buds,  and 


THE  EQUISETACEyE. 


these,  upon  developing,  become  cither  secondary  root- 
stocks  pushing  up  toward  the  surface,  or  possibly  aerial 
stems  rising  above  it.  From  the  base  of  these  buds  slen- 
der roots  are  produced.  The  sections  of  the 
rootstocks  are  covered  with  a  tawny  or  blackish 
felt,  which,  like  the  root-hairs,  doubtless  assists 
in  the  work  of  food-absorption.  The  buds  on 
the  stems  readily  produce  roots  if  covered  with 
moist  earth,  while  rootstocks  exposed  to  the  air 
soon  produce  stems.  Since  the  plants  are  liable 
to  be  either  covered  with  mud  or  washed  from 
their  places  during  freshets,  it  is  a  wise  provi- 
sion of  Nature  that  stem  and  rootstock  are^  so 
nearly  interchangeable.  In  certain  species  the 
rootstock  occasionally  develops  small  round  [|l| 
tubers.  These  resemble  the  rootstock  in  struc- 
ture and  may  be  assumed  to  be  undeveloped 
branches  of  it.  Their  use  is  unknown,  unless 
they  may  serve  as  a  storehouse  for  surplus  plant- 
food.  Under  certain  circumstances  they  may 
possibly  give  rise  to  new  plants. 

,-p,,  ...      -  A  Joint  of 

ine  spores  are  always  borne  at  the  tips  of  the   the  stem. 
stems    in  cone-like  spikes   or   catkins.       These 

spikes  consist  of  numerous,  usually 
six-angled,  plates  attached  to  the  stem 
by  a  central  stalk,  and  bearing  from 
five  to  nine  little  sacs  or  spore-cases 
on  their  margins.  The  sacs  extend 
SPORE-CASES.  horizontally  toward  the  centre  of  the 
cone,  and  only  the  angular  plates  to  which  they  are 
attached  are  to  be  seen  before  maturity.  When  ripe  the 
cone  lengthens  slightly,  drawing  the  plates  apart,  the 
spore-cases  open  on  the  side  next  the  stalk  that  bears 
them  and  the  spores  escape. 


14 


THE  EQUlSETACE^e. 


The  spores  are  tiny  globular,  single-celled  bodies, 
bright  green  in  colour,  and  so  small  that  single  indi- 
viduals cannot  be  distinguished  without  a  lens.  Each 
posse«""s  two   filiform    appendages  with  enlarged  ends, 

called  elaters, 
w  h  i  c  h  are  at- 
t  a  c  h  e  d  to  the 
equator  of  the 
spore  by  their 
middle,  coiling 
spirally  around  it 
when  moist  and 
spreading  out 
when  dry.  As 
the  spore  -  case 
dries  at  maturity, 
the  elaters  uncoil 
and    assist    in 


SPORES,  ENLARGED. 


iberating       the 


spores ;  and  when  the  spores  are  free,  they  assist  in  float- 
ing them  on  the  air.  The  elaters  of  several  spores 
often  become  entangled,  and  the  spores  float  away  to- 
gether, an  advantageous  arrangement,  since  the  prothallia 
are  dioecious  and  require  more  than  one  spore  to  repro- 
duce a  plant. 

The  spores  contain  chlorophyll,  the  green  colouring- 
matter  of  plants,  and  lose  their  power  of  germinating 
within  a  few  days  after  leaving  the  spore-case.  When 
they  lodge  in  a  favourable  place,  they  germinate  in  ten  or 
twelve  hours,  and  soon  produce  small  green,  lobed  pro- 
thallia. It  is  said  that  the  fresh  spores  will  germinate 
readily  if  sown  upon  the  surface  of  water.  Although 
the   spores   are  apparently  all  alike,  some   produce  only 


THE  EQUISETACE^.  15 

male  and  others  only  female  prothallia.  It  is  impossi- 
ble, before  germination,  to  discover  which  is  which,  and, 
since  the  male  prothallium  is  always  the  smaller,  it  is 
conjectured  that  the  difference  in  the  sex  may  be  due 
entirely  to  the  amount  of  nourishment  the  prothallia  are 
able  to  obtain,  those  well  nourished  becoming  female 
and  the  others  male.  It  is  interesting  to  know  that  the 
cones  of  fossil  species  have  been  found  so  well  preserved 
as  to  show  that  the  ancestors  of  our  present  plants  had 
spores  of  two  kinds,  like  the  modern  selaginellas  and 
isosetes. 

The  scouring-rushes  range  in  height  from  a  few  inches 
to  thirty  feet,  but  the  largest  seldom  exceed  two  inches 
in  diameter,  and  the  majority  are  rarely  thicker  than  a 
lead  pencil.  In  all,  the  rootstock  at  least  is  perennial, 
and  in  some  the  aerial  stems  last  for  several  years. 
There  are  about  twenty  living  species, .i^iost  of  them  in 
temperate  regions.  During  the  Carboniferous  Age  they 
were  most  abundant,  almost  equalling  the  ferns  in  num- 
bers. Though  few  in  species  now,  they  are  abundant 
and  widely  distributed.  North  America* contains  repre- 
sentatives of  more  than  half  of  all  the  species  in  the 
world. 

The  name  Eqiiisctinii  is  from  two  Latin  words  mean- 
ing **  horse  "  and  ''  bristle,"  and  was  applied  to  these 
plants  in  allusion  to  the  many  slender  branches  of  cer- 
tain species,  which  render  the  plants  not  unlike  the  tail 
of  ahorse  in  appearance.  In  the  order  Equisetales  there 
is  but  one  living  family,  the  Equisetace^e,  and  in  this 
family  there  is  but  the  single  genus  Eqiiisetum.  The 
fossil  species  mostly  belonged  to  the  family  Calamarise. 
Many  of  them  attained  the  size  of  trees. 


Key  to  the  Species  of  Equisetum. 


Series  I.  —  Evergreen  species.     Stems  rough,  seldom  branched, 
catkins    usually  tipped    with    a   hard 
point 
Stems  tall,  stout,  about  as  thick  as  a  lead  pencil 
Sheaths  dilated  upward 

Margins  incurved,  stems  rough 

E,  Fimstoiii 
Margins  not   incurved,  stems   smooth 
E.  lanngattim 
Sheaths  not  dilated  upward 

Old  stems  much  branched  E.  i-obnstn7)i 
Old  stems  seldom  branched 

Joints  short.  .      E.   hieinale 

Joints  longer  .      E.  Ferrisst 

Stems  slender,  tufted 

Six-angled-,  thread-like  E.  scirpoides 

More  than  six-angled,  larger    E.  variegatu}7i 
Series  II.  —  Deciduous  species,    Rootstock  only,  perennial. 
Stems  smooth,  usually  branching,  catkin 

not  tipped  with  a  hard  point 
Fertile  stems  tawny  or  flesh-coloured  when  young 
Not  lasting  through  the  summer 

Plants  stout.  Western     .         E.  Telmateia 
Plants  slender,  mostly  Eastern  E.  arvense 
Lasting  through  the  summer 

Branches  of  sterile  stems  unbranched 

E.  pratense 
Branches  of  sterile  stems  again  branched 
E.  silvaticujn 
Fertile  stems  green  like  the  sterile 

Sheaths  appressed        .  E,  fhiviatfU 

Sheaths  looser 

Spores  perfect,  abundant     E.  palusire 
Spores  imperfect,  few  E.  littorale 


THE    EVERGREEN     EQUISETUMS, 
OR  SCOURING-RUSHES. 


THE  SCOURING-RUSHES 


of  the  most  conspicuous  differ- 
ences among  the  equisetums 
is  found  in  the  duration  of 
the  aerial  stems.  In  some 
species  all  traces  of  them 
above  ground  disappear  soon 
after  the  first  hard  frost, 
while  in  others  the  stems  not 
only  endure  at  least  one  win- 
CROSS-SECTioN  OF  STEM.  tcr,  but  in  the  second  season 

possess  enough  vitality  to  put  forth  new  branches. 
It  is  singular,  also,  that  the  evergreen  species  should 
all  resemble  one  another  in  external  appearance  more 
than  they  do  the  species  with  deciduous  stems.  To 
divide  the  genus  upon  the  single  character  of  jjerennial 
or  deciduous  stems  would  separate  the  species  into  two 
very  natural  groups.  It  has  been  proposed  to  make 
these  two  groups  separate  genera,  though  botanists  at 
present  usually  include  the  two  in  the  single  genus 
Eqiiisetuju  ;  the  evergreen  specie^s,  however,  are  placed 
in  the  sub-genus  Hippochc^tcB, 


The   Common    Scouring- Rus/j. 

Undoubtedly  the  best  known  of  the  evergreen  equise- 
tums is  the  common  scouring-rush  {Eqtiisetnin  Jiiemale). 
Its  stiff  unbranched  stems  of  dark  green,  ringed  at  the 


20 


THE  SCOURING-RUSHES. 


nodes  with  bands  of  black  and  ash-colour,  are  sufficient 
to  attract  the  eye  at  any  time  of  the  year,  but  they  are 
especially  noticeable  in  winter,  when,  in  the  absence  of 
other  greenery,  they  become  very  conspicuous  against  a 
background  of  snow  or  withered  leaves.  It  is  a  very  gre- 
garious species,  and  is  seldom  found  except  in  little 
thickets  that  are  very  characteristic. 

Early  in  spring  the  new  stems  make  their  appearance, 
arising  from  short  branches  of  the  underground  portion  of 
the  plant.  In  appearance  these  budding  stems  suggest  a 
closed  telescope,  being  of  full  diameter,  but  with  only 
the  sheaths  of  the  joints  showing.     Development  consists 

in    the    lengthen- 
ing of    the  inter- 
nodes,   just    as  a 
telescope      may 
be  lengthened  by 
drawing   out   the 
tube,    though    in 
the    case    of    the 
plant  the  sections 
are  not  enclosed  one  within  the  other,  as  in  the 
instrument.     The  full-grown    stems   are  usually 
stiffly  erect  and  unbranched  the    first  year;  but 
during  the  second  season,  if  the  tip  of  the  stem  is 
injured,  a  few  of  the  upper  nodes  may  put  forth 
small   branches.       These,  instead    of   diverging, 
grow  upward,  nearly  parallel  with  the  main  stem. 
The  height  of  the  stem  seems  limited  only  by 
its  capacity  for  growth,  though,  since  each  joint 
Items,   is  smaller  than  the  one  preceding  it,  there  w^ould 
come  a  time,  theoretically,  when  no  more  joints 
could    be   produced.     The    tip    of    the    stem    is  usually 


THE  SCOURING-RUSHES.  21 

winter-killed  long  before  such  a  condition  is  reached. 
Mature  stems  seldom  reach  a  height  of  more  than  four 
feet,  or  a  diameter  at  base  of  half  an  inch. 

A  series  of  joints  in  the  stem  divide  it  into  many  sec- 
tions, each  three  or  four  inches  long.  At  the  top  of  each 
section,  or  internode,  there  is  a  Icaf-sheath  a  quarter  of 
an  inch  or  more  long,  fitting  closely  around  the  base  of 
the  next  internode,  and  bearing  on  its  summit  numer- 
ous small  triangular  teeth  which  end  in  a  long  point. 
These  teeth  are  jointed  to  the  sheath  and  usually  fall 
away  at  maturity,  being  noticeable  only  in  very  young 
stems.  Often  the  tips  coalesce  in  the  bud,  and,  as  the 
stem  lengthens,  they  are  carried  upward  on  its  summit 
in  a  compact  mass  resembling  an  old-fashioned  candle- 
extinguisher  or  a  Chinese  pagoda. 

Where  the  sheath  joins  the  stem,  there  is  a  brown  or 
blackish  band,  and  a  line  of  the  same  colour  borders  the 
outer  edge.  Between  these  the  colour  is  purplish,  green- 
ish, or  ashy  white.  The  width  of  the  black  band  and  the 
colour  between  them  varies  with  age  and  with  the  indi- 
vidual. In  some  specimens  the  bands  always  remain  nar- 
row, while  in  others  they  may  broaden  until  the  entire 
sheath  is  suffused  with  black.  This  latter  is  most  com- 
mon in  old  stems  and  in  sheaths  near  the  base.  The 
marginal  band  is  always  the  darker  of  the  two,  and  in 
young  specimens  the  second  band  is  frequently  missing, 
or  is  indicated  only  by  a  faint  brown  line.  No  species 
show  the  manner  of  jointing  better  than  this.  After  the 
stem  has  been  pulled  apart  it  may  be  easily  reconstructed 
on  account  of  the  nicety  with  which  the  ends  of  the 
internodes  fit  into  the  sheaths.  At  the  nodes  or  joints 
the  stem  is  solid,  but  cross-sectionS/ of  the  internodes 
show  a  very  large  central  cavity  occupying  four  fifths  of 


THE  SCOURING-RUSHES. 


the  stem,  besides  a  series  of  small  oval  vallccular  canals 
alternating  with  a  series  of  still  smaller  carinal  canals  in 
the  thin  walh.  Externally  the  stem  bears  from  twenty 
to  thirty  or  more  narrow  longitudinal  grooves,  the  ridges 
between  them  being  covered  with  many  minute  cross- 
bands  of  silex.  Occasionally  these  bands  break 
down  in  the  centre,  leaving  a  double  row  of 
silicious  tubercles.  The  amount  of  silex  in  the 
outer  coat  varies,  but  usually  it  so  completely 
covers  the  epidermis  that  the  vegetable  matter 
can  be  dissolved  out  by  acids,  leaving  a  com- 
plete outline  of  the  stem  in  silex, —  a  sort  of 
stone  or  glass  skeleton. 

The  scouring-rush  fruits  in  a  yellowish,  cone- 
like catkin  at  the  apex  of  the  stem.  Occasion- 
ally, during  the  second  summer,  small  cones 
may  be  produced  at  the  tips  of  the  short 
branches  also.  The  terminal  cone  is  ovate, 
about  half  an  inch  long,  and  ends  in  a  short 
hard  point.  The  principal  fruiting-season  is  in 
May  and  June,  though  the  cones,  usually  small 
and  undeveloped,  may  be  found  at  any  time, 
and  the  plant  fruits  in  a  desultory  way  until 
October.  Even  in  winter  the  compact  little 
cones  have  fully-formed  spores  packed  snugly 
away  until  a  more  propitious  season.  If  one 
of  these  winter  cones  be  split  from  tip  to  base 
with  a  sharp  knife,  and  the  cut  surface  be 
quickly  examined  with  a  lens,  a  most  interest- 
COMMON     inor  sight  will  be  revealed.       From   the    gaps 

SCOURING-         t'        i5  fat 

RUSH.       made  in  the  delicate  walls  of  the  spore-cases, 

EquisetU7)i  * 

hiemaie.      ^  Hvcly  crowd  of  spores  come    tumbling  out, 
jostling     one    another    in    their    haste     and     apparently 


THE  SCOURING-RUSHES.  23 

urged  on  by  those  behind.  As  each  fat  little  spore 
reaches  the  open,  it  unfolds  its  elaters  like  four  tiny  wings 
and  quickly  sails  out  of  the  field.  As  long  as  the  mois- 
ture in  the  tissues  is  evaporating  they  continue  to  come. 
To  change  the  scene,  one  has  only  to  dip  his  specimen 
into  water  or  to  breathe  upon  it.  At  once  every  elater  is 
coiled.  Even  those  spores  just  balanced  on  tip-toe  as  it 
were,  ready  for  flight,  decide  to  remain,  and  all  seem 
trying  to  shrink  into  the  smallest  space  possible.  The 
change  is  due  to  the  hygroscopic  nature  of  the  elaters, 
which  coil  in  the  presence  of  moisture.  This  character- 
istic ensures  that  the  spores  shall  not  set  out  on  their 
travels  until  a  fair  day  comes  and  the  sailing  is  good,  and 
also  prevents  the  elaters  from  being  folded  again  and  the 
spores  dropped  until  a  moist  interval,  suitable  for  ger- 
mination, occurs. 

The  rough  and  flinty  exterior  of  this  species  makes  it 
useful  for  scouring  and  polishing.  It  was  once  of  prime 
importance  in  domestic  affairs,  being  used  for  cleaning 
pots,  pans,  floors,  and  other  woodwork.  Cabinet-makers 
and  others  also  found  many  uses  for  it,  but  with  the 
advent  of  scouring-soaps  and  sandpaper  it  has  gradually 
fallen  into  disuse.  In  our  own  country,  a  few  Indians 
on  the  borders  of  civilization  still  use  it  for  polishing 
the  shafts  of  arrows  and  similar  work.  It  is  said  to  be 
occasionally  used  in  the  Old  World  also  at  the  present 
day. 

The  names  of  "  scouring-rush,"  ''  scrub-grass,"  ''  shave- 
grass,"  *' polishing-rush,"  and  "  gunbright  "  all  allude  to 
its  use  in  polishing,  while  the  term  ''naked  horsetail" 
has  reference  to  the  branchless  nature  of  the  stems.  In 
some  sections  the  slender  jointed  stems  have  suggested  the 
name    of    ''bamboo."     "Joint-rush"    and   "joint-grass" 


2A  THE  SCOURING-RUSHES. 

refer  to  the  same  appearance.  The  names  '*  snake-weed  " 
and  *'  snake-rush  "  are  probably  derived  from  the  fact 
that  these  plants  often  grow  near  water, — damp  thickets 
and  snakes  being  alvv^ays  popularly  associated.  The 
author  has  also  heard  the  stems  called  **  frogs'  fishing- 
poles."  The  species  has  occasionally  been  called 
"  smoke-weed  "  or  **  mountain-rush,"  but  the  reason  for 
the  application  of  these  names  is  not  apparent.  **  Horse- 
pipes  "  refers  to  the  large  size  of  this  species.  Smaller 
species  are  called  **  pipes"  or  **  paddock-pipes,"  and  the 
larger  ones  would  naturally  be  called  **  horse-pipes,"  just 
as  we  speak  of  **  horse-radish  "  '*  horse-fiddle,"  or  *'  horse- 
chestnut."  *' Winter-rush  "  alludes  to  the  fact  that  this 
is  our  commonest  evergreen  species.  At  the  time  of  its 
use  as  a  scouring-agent  it  was  imported  into  England 
from  Holland  in  large  quantities,  and  in  this  way  gained 
the  name  of  **  Dutch  rush."  It  is  stated  that  this  species 
is  often  planted  upon  the  dykes  in  Holland,  its  long 
branching  rootstocks  serving  to  prevent  the  soil  from 
washing  away. 

Children  often  amuse  themselves  by  placing  the  fresh 
stems  on  the  rails  of  the  street-car  lines,  and  listening  for 
the  sharp  reports  caused  by  the  air  in  the  central  cavity 
bursting  through  the  walls  of  the  stems  as  the  car  passes 
over  them.  The  juices  of  the  stem  will  also  cause  them 
to  explode  when  thrown  into  the  fire,  and  the  medicine- 
men of  various  Indian  tribes  still  make  use  of  them  in 
this  way,  in  order  that  their  popping  may  stimulate 
their  patients  to  renewed  vigour.  The  hollow  joints  of 
the  stem  may  be  made  into  a  rude  sort  of  Pan-pipe  simi- 
lar to  those  made  from  canes  by  the  negroes  of  the  South. 
According  to  an  old  writer  it  was  thought  that  if 
cows  fed  upon  this  plant  their  teeth  would  drop  out.     It 


THE  SCOURING-RUSHES.  25 

may  be  added  that  cattle  will  not  eat  it  if  there  is  any- 
thing else  to  be  had.  The  juice  of  the  plant  was  once 
thought  to  be  useful  in  nosebleed  and  as  an  application 
to  wounds. 

The  scouring-rush  is  found  throughout  North  America 
growing  along  streams,  on  the  borders  of  swamps,  and  in 
other  low  grounds.  It  is  able  to  exist,  however,  with 
much  less  moisture,  and  is  frequently  abundant  along  dry 
railway  embankments  and  on  gravelly  banks.  There  is 
some  variation  in  plants  from  different  localities,  the  one 
here  described  being  the  form  common  to  the  North- 
eastern States.  Its  closely  appressed  sheaths  and  many- 
grooved  stems  are  characters  that  usually  serve  to  identify 
it.  It  is  the  most  abundant  of  our  evergreen  species,  and 
is  also  found  in  Europe  and  Asia,  extending  in  a  more  or 
less  broad  belt  around  the  earth  in  the  North  Temperate 
Zone.  It  appears  to  be  absolutely  unharmed  by  the  cold. 
The  water  in  the  central  hollow  often  freezes  solid  without 
hurt  to  the  plant.  In  exposed  situations  the  stems  o.n  the 
southern  side  turn  a  dingy  brown  in  winter,  but  become 
green  again  on  the  approach  of  a  milder  season. 

In  the  Mississippi  Valley,  and  farther  west,  there  is  a 
form  called  Equisetum  Jiiemale  internicdiiuii  which  has 
transverse  bands  of  silex  on  the  stems,  looser,  somewhat 
funnel-shaped  green  sheaths  with  a  narrow  black-and- 
white  margin  and  deciduous  or  persistent  teeth.  It  has 
often  been  collected  for  i5"^//z>^/?/;;/  lcevigat2U)i,\\A\\Q\\  it 
resembles  in  many  ways,  especially  in  the  funnel-shaped 
sheaths,  but  the  internal  structure  is  that  of  true  Jiiemale. 
Equisetum  Icevigatum  is  also  said  to  have  annual  stems, 
but  there  is  still  some  doubt  upon  this  subject.  In  some 
States,  notably  Nebraska,  Equisetum  hiemale  intermedium 
is  considered  of  some  importance  as  a  forage  crop.     No 


26 


THE  SCOURING-RUSHES. 


less  than  ten  named  varieties  of  Equisetiim  hiemale  have 
been  reported  from  America.  Many  of  these  are  mere 
ecological  forms,  of  interest  only  to  the  systematist. 
Those  wishing  to  study  them  will  find  a  full  account  of 
all  in  volume  XI  of  the  Fern  Bulletin. 


The    Great  Scouring-Rush. 

In  the  Southern  and  Western  States  the  most  abun- 
dant of  the  scouring-rushes  is  probably  the  great  scour- 
ing-rush  {Eqiiisetjc/n  robusttmi),  which  is  supposed  to 
intergrade  with  the  common  scouring-rush  and  is  by 
many  considered  only  a  variety  of  it.  It  is  a  strong  and 
robust  species,  but  except  for  its  larger  size  it  cannot  be 
distinguished  from  Eqiiisetiim  hiemale  in  a 
cursory  examination.  Mr.  A.  A.  Eaton, 
who  has  carefully  studied  the  genus,  is  con- 
vinced that  this  is  only  a  well-marked  race 
Ij  of  the  scouring-rush,  but  as  it  has  always 
appeared  in  text-books  as  a  separate  species 
it  will  be  so  treated  here.  Mr.  Eaton's 
view  is  probably  the  correct  one,  however. 
Aside  from  its  larger  size,  the  character- 
istics usually  depended  upon  for  separating 
Equisetiim  robustum  from  Equisetum  hiemale 
are  the  greater  number  of  grooves  in  the 
stem,  the  three-keeled  ridges  of  the  sheaths, 
and  the  sinfjle  series  of  cross-bands  of  silex  on 
Equisetum  hiemale  is  supposed  always  to 
have  obscurely  four-keeled  ridges  in  the  sheaths,  and  two 
rows  of  silex  tubercles  on  the  carinae,  but  any  of  the 
characteristics  of  the  one  may  be  matched  by  specimens 
of  the  cnher. 


Large  Sheath. 
Natural  Size. 

the  carina:. 


THE  SCOURING-RUSHES.  27 

In  favourable  situations  the  stems  of  this  species  often 
reach  a  height  of  ten  feet,  and  a  diameter  of  half  an  inch 
or  more  at  base,  forming  thickets  similar  to  those  of  the 
common  scouring-rush.  In  the  warmer  parts  of  its 
range  the  new  shoots  begin  to  make  their  appearance 
in  March  or  earlier,  and  by  the  first  week  in  April  the 
fruiting  cones  may  be  obtained,  though  the  stems  have 
scarcely  reached  their  maximum  height  at  that  period. 
During  the  first  year  the  stems  seldom  branch,  but  early 
the  next  spring  a  large  number  of  them  put  forth  long 
wand-like  branches  from  the  upper  joints.  All  authori- 
ties agree  that  this  form  rarely  branches,  but  this  is 
clearly  a  mistake.  It  produces  branches  much  more 
freely  than  does  Equisetiini  Jiieniale.  In  addition  to  the 
principal  stems  this  species  not  infrequently  produces 
several  slender  stems  from  each  rootstock. 

The  sheaths  are  rather  longer  than  those  of  Equisetum 
Jiieniale,  and  are  pinkish  ash-colour  with  rather  narrow 
marginal  and  basal  dark  bands,  the  latter  at  first  promi- 
nent and  lighter  in  colour.  The  teeth  are  dark  brown 
with  tawny  margins,  elongated  triangular  in  shape,  with 
long  tapering  points,  and  usually  remain  in  position 
until  the  stems  are  full  grown  or  even  longer.  Those 
upon  the  branches  do  not  fall  off  during  the  life  of  the 
stems. 

The  fruiting  cones  are  from  half  an  inch  to  an 
inch  long  and  terminate  in  a  sharp  point  as  in  the 
other  species  of  this  group.  The  fertile  stems  produce  a 
single  spike  at  the  apex  of  the  stem  the  first  year,  and 
the  following  season  one  or  more  smaller  cones  may  de- 
velop on  the  ends  of  small  branches,  the  terminal  cone,  of 
course,  being  absent.  Like  the  common  scouring-rush, 
the  stem  of  this  species  is  hollow  for  the  greater  part  of 


28  THE  SCOURING-RUSHES. 

its,  diameter,  and    the  contained  air  causes   a  loud 
report  when  it  is  forced  out  under  pressure. 

The  great  scouring-rush  is  rare  east  of  the  Mis- 
sissippi River  except  in  the  South.  It  has  been 
reported,  apparently  upon  good  authority,  from 
scattered  stations  in  New  Jersey,  Pennsylvania, 
Maryland,  Indiana,  Illinois,  and  Michigan,  and  is 
the  common  form  in  the  States  bordering  the  Gulf. 
In  the  West  it  appears  to  be  plentiful  throughout, 
extending  northward  into  British  Columbia.  It 
is  said  to  occur  in  India  also.  The  stems  are  as 
rough  as  those  of  the  common  species,  and  are  still 
occasionally  used  for  polishing  by  the  Southern 
negroes.  Being  so  nearly  like  Ji^iiisetiim  Jiieniale  \\. 
shares  with  it  the  various  common  names. 

The    Slender   Scouring- Rush. 

The  characters  relied  upon  for  the  identification 
of  the  various  Equisctiini  species,  such  as  the  num- 
ber of  grooves  in  the  stem,  the  diameter  of  the 
stem,  length  of  the  joints,  etc.,  make  the  variations 
a  matter  of  easy  mathematical  demonstration.  In 
making  some  investigations  along  this  line,  recently, 
the  author  was  surprised  to  find  that  the  extremes 
of  variation  in  Eqiiisetvm  Jiicviale  are  much  less 
than  is  commonly  supposed.  Out  of  more  than 
250  stems  selected  at  random,  all  but  twenty-four 
were  between  5/32  and  8/32  of  an  inch  in  diam- 
eter. The  length  between  joints  was  between 
two  and  three  inches  in  all  but  fifteen  of  the 
Equisetum  230  spccimcus  mcasurcd,  while  of  125  speci- 
Seciion  of     mcus  in   which  the  g^rooves    were    counted,  all 

Stem,  ^ 

Natural      but    thirteen  had    from    twenty-four    to    thirty 


THE  SCOURING-RUSHES.  29 

grooves  eacli.  At  the  same  time,  an  Eqiiiseinui  was 
found  near  Joliet,  Illinois,  that  differed  so  constantly 
in  these  characters  that  it  was  considered  a  new  species 
and  was  named  Eqiiisetuin  Ferrissi.  This  species  is 
principally  distinguished  by  its  tall,  slender,  pale-green 
stems  with  few  grooves,  and  the  exceedingly  long 
sections  between  joints.  More  than  fifty  specimens, 
selected  at  random,  were  measured,  and  all  but  four 
were  4/32  of  an  inch  or  less  in  diameter.  The  grooves 
were  also  fewer  in  number,  only  nine  stems  having  more 
than  fourteen  grooves.  The  greatest  difference  of  all, 
however,  was  in  the  length  between  joints.  None  of 
the  intern  odes  were  as  short  as  the  average  in  Equisetiiui 
hiemale,  and  but  fourteen  were  less  than  four  inches  long. 
The  longest  measured  more  than  six  and  a  half  inches. 
This  form  may  also  be  known  by  the  appressed  sheaths, 
which  are  green  when  young,  but  in  age  become  chalky- 
white  with  a  narrow  black  basal  band  encircling  them 
obliquely.  The  teeth  are  two  thirds  the  length  of  the 
sheaths,  slender  and  deciduous,  with  a  central  streak  of 
dark  brown  bordered  by  a  wider  hyaline  margiq.  After 
the  teeth  have  fallen,  the  border  of  the  sheath  becomes 
thickened,  incurved,  and  dark  brown  in  colour.  The 
grooves  between  the  leaves  extend  below  the  basal  black 
band.  The  catkins,  like  those  of  the  common  scouring- 
rush,  are  tipped  with  a  sharp  point  and  are  borne  on  a 
short  pedicel.  They  ripen  about  the  first  of  June,  but 
many  appear  to  be  abortive  and  are  to  be  found  in  the 
globular  expansion  formed  by  the  topmost  whorl  of 
leaves. 

The  slender  scouring-rush  resembles  Eqiiiset2iin  Jiiemale 
intermedium,  but  may  be  distinguished  from  it  by  the 
smoother,  slenderer    stems,  by  having  fewer  grooves  in 


30  THE  SCOUKINORUSHES. 

the    stem,  and    by    the    appressed    sheaths  and  strongly 
apiculate  catkin. 

It  is  not  known  at  present  whether  this  form  occurs 
elsewhere,  or  whether  its  existence  at  Joliet  is  unique. 
At  the  place  where  it  was  discovered  it  forms  an  exten- 
sive thicket,  but  this  may  have  arisen  by  means  of  the 
spreading  rootstock.  Possibly  the  first  plant  was 
produceci  by  a  variant  spore.  If  so,  it  is  not 
ikely  to  be  found  in  other  localities,  and  the 
question  arises  whether  it  is  entitled  to  be  called 
a  species,  or  is  more  properly  considered  a  form 
of  Equisctuni  liiciualc.  From  the  modern  view- 
point of  evolution  it  might  be  thought  an  off- 
shoot, by  mutation,  of  the  species  mentioned. 
In  form  it  appears  to  be  more  distinct  than  either 
Eqiiuctinn  Jiieniale  robiistiiin  or  Eqiiisetiim  hiemalc 
STEM  ^^.intermedituii;  but  should  it  turn  out  to  be  un- 
LARGED.  ^^Q,.^hy  q{  specific  rank  it  would  still  rank  as  a 
sub-species   with  the  title  of  Equisetum  hiemale  Ferrissi. 

The  Smooth  Scouring- Rush. 

Typical  specimens  of  the  equisetums  are  not  difficult 
to  identify,  but  when  one  has  a  large  series  of  a  single 
species  from  different  localities  to  deal  with,  the  task 
becomes  more  perplexing  than  might  be  supposed,  on 
account  of  the  numerous  variations  presented  ;  in  fact, 
it  is  hinted  that  all  the  species  in  the  section  HippocJicetc, 
though  distinct  enough  as  to  type,  may  be  connected  by 
intergrading  forms.  One  of  the  most  variable  of  these 
species  is  the  smooth  scouring-rush  {Equisetum  hcviga- 
tuin).  On  the  one  hand  it  is  linked  to  the  common 
scouring-rush  by  the  form  known  as  Equisetum  Jiiemali 


SMOOTH  SCOURING-RUSH. 
Equisetum  lcr7>igatuni. 


THE  SCOURING-RUSHES.  31 

intcrmediuDi,  and  on  the  other  it  intergrades  ahnost 
imperceptibly  with  the  smaller  variegated  scouring-rush. 

In  outward  appearance  the  smooth  scouring-rush  is 
much  like  Equisetiim  hiemale,  though  usually  shorter 
and  slenderer  and  with  less  silex  in  the  epidermis. 
Well-developed  specimens  may  reach  the  height  of  four 
feet,  but  the  average  is  probably  less  than  twenty  inches. 
The  exterior  is  comparatively  smooth  and  has  from  ten 
to  thirty  grooves.  The  sheaths  are  long-,  green,  and 
dilated  upward  like  a  funnel,  this  last  characteristic 
being  one  of  its  most  distinguishing  features.  There 
seems  to  be  some  question  as  to  whether  or  not  the 
stems  last  through  the '  winter.  All  its  affinities  are 
with  the  evergreen  species,  and  it  has  always  been 
called  evergreen  in  the  books,  but  Mr.  Eaton,  the 
latest  monographer  of  the  American  species,  has  stated 
that  the  stems  are  annual,  and  that  the  species  may 
be  distinguished  from  Equisetiim  hiemale  by  this  single 
peculiarity.  Further  observations  on  this  point  are 
desirable.  The  present  lack  is  no  doubt  due  to  the 
fact  that  the  species  is  rare  in  the  Eastern  States,  where 
most  of  the  studies  of  Eqtiisetiun  have  been  made. 

The  stems  of  the  smooth  scouring-rush  usually  grow 
in  tufts  from  the  summit  of  the  rootstock.  They  are 
slender  and  usually  unbranched,  though  the  more  robust 
specimens  may  develop  several  ascending  branches  from 
near  the  base,  especially  if  the  tip  be  injured.  In  this 
it  is  the  reverse  of  the  common  scouring  rush,  which,  if 
it  branches  at  all,  does  so  near  the  tip  of  the  stem.  In 
colour  the  stems  are  pale  green,  and  a  cross-section  shows 
a  large  central  cavity  with  medium-sized  vallecular 
canals,  those  under  the  carinae  being  either  smaller  or 
absent.     On     the    exterior    the    grooves    are    somewhat 


32 


THE  SCOURING-RUSHES. 


rounded  with  or  without  cross-bands  of  silex.  The 
sheaths  are  coloured  like  the  stem,  or  occasionally 
paler,  rarely  with  a  black  girdle  at  base.  The  leaves 
of  the  sheaths  usually  have  a  central  ridge 
at  base,  which  fades  out  as  the  apex  is 
approached.  The  teeth  are  long  and  slen- 
der, silvery  white  in  colour,  with  a  narrow 
streak  of  dark  brpwn  down  the  middle.  At 
maturity  these  teeth  usually  fall  away,  leav- 
ing the  brownish  bases,  bordered  with  white, 
as  a  narrow  brown  and  white  margin  to  the 
sheath. 

This  species  begins  to  fruit  about  the 
first  of  May,  though  the  catkins  may  be 
found  as  late  as  midsummer.  The  late 
catkins  are  produced  on  secondary  stems 
which  spring  from  the  base  of  the  earlier 
ones.  The  cones  are  small,  ovate 
or  oblong,  with  the  base  often  en- 
closed in  the  uppermost  sheath,  and 
the  point  at  apex  short  or  absent. 

The  range  of  the  smooth  scouring- 
rusli,  as    usually    defined,  begins   in 
New  Jersey  and  spreads  out  in  fan 
shape   to  the  Pacific  coast,  the  line  of  its  south- 
ern limit  passing  through  Louisiana  and  Texas, 
while  the  line    on  the    north    crosses    Ohio  and 
Wisconsin,  and  so  on  to  British   Columbia.     In 
the  East  and  South  it  is  extremely  rare,  and  there 
is  a  suspicion  that  the  Eastern  records  are  based  catkinof 
on  forms  that  are  more  properly  referred  to  Equi-  sc^u°dng- 
setmn  hiemale.  The  form  Equisetum  hiemale  inter-    ^"*^' 
medium  closely  resembles  it,  especially  in  the  shape  of  the 


SHEATH  OF 

SMOOTH 

SCOURING- 

RUSH. 


THE  SCOURING-RUSHES.  33 

sheaths,  though  in  the  latter  these  are  shorter  and  paler, 
with  a  black  basal  girdle.  Eqtiisetum  IcEvigatum  is  found 
only  in  America,  and  is  doubtless  most  common  in  the 
Middle  West,  where  it  is  often  used  for  forage.  It  pre- 
fers a  moist  soil,  being  usually  found  in  sand  or  clay  on 
the  borders  of  streams.  Many  facts  in  its  life  history  are 
as  yet  imperfectly  known,  and  the  beginner  will  find  this 
a  species  worthy  of  further  observation.  Five  American 
varieties  of  no  especial  importance  have  been  described 
in  the  Fern  Biillctin. 

The  Branched  Rquisetum. 

Students  who  consult  other  works  on  the  fern  allies 
will  find  listed  among  the  North  American  species  two 
that  are  no  longer  regarded  as  members  of  our  flora. 
These  are  EqjiisetJivi  ramosissiimim  ixwd  Eqiiisetmn  Mcxi- 
caniim.  The  first  was  reported  from  British  Columbia 
more  than  fifty  years  ago,  but  as  it  has  never  been 
rediscovered  there,  and  the  reported  situation  is  far  out 
of  the  plant's  known  range,  it  seems  almost  certain  that 
some  other  species  was  mistaken  for  it.  The  second 
species,  Equisettini  Mcxicamim,  has  frequently  been 
reported  from  southern  California,  but  here  again  the 
probabilities  are  that  the  identification  is  incorrect. 
Baker,  in  his  *'  Hand-Book  of  the  Fern  Allies,"  considers 
Equisetiun  Mexicaimm  to  be  a  form  of  the  tropical  Equi- 
settim  giganteiim  ;  and  while  it  is  possible  that  an  occa- 
sional plant  of  this  species  may  stray  across  our  south- 
western border,  it  is  more  probable  that  the  California 
specimens  belong  to  a  different  species.  Since  these 
plants  have  always  been  wrongly  identified,  it  becomes 
necessary  to  give  them  a  new  name  to  distinguish  them. 


34  THE  SCOURING-RUSHES. 

Mr.  A.  A.  Eaton  has  therefore  proposed  the  name  of 
Eqiiisetum  Ftinstoni,  in  honour  of  General  Funston,  who 
in  early  life  made  several  botanical  expeditions  into 
little-known  regions,  upon  one  of  which  he  collected  this 
species. 

The  branched  scouring-rush  is  most  like  Equisetum 
Icevigattivi,  but  may  be  distinguished  from  it  by  its 
rougher  stems  and  by  the  shape  and  make-up  of  the 
sheaths.  In  both  species  the  sheaths  are  coloured 
like  the  stems,  and  both  are  dilated  upward,  but 
in  Equisetum  Funstoni  the  margin  of  the  sheath, 
after  the  tips  have  fallen,  turns  inward,  while  in 
Equisetum  Icevigatum  it  does  not.  The  leaves 
composing  the  sheaths  of  Equisetum  Funstoni  are 
somewhat  separated  at  the  apex.  The  stems  of 
Equisetum  icevigatum  are  also  supposed  to  be 
annual,  while  those  of  Equisetum  Funstoni  last 
through  the  winter.  This  difference,  however, 
may  be  accounted  for  by  the  warmer  climate  of 
the  region  inhabited  by  the  latter.  Both  species 
Sheath  of  ^^^  alike  in  having  catkins  lacking  the  apical 
^FunsfonT.  poi^t,  tliougli,  curiously  enough,  they  belong  to 
a  section  in  which  the  possession  of  such  a 
point  is  one  of  the  distinguishing  features.  It  has  been 
suggested  that  Equisetum  Funstoni  is  but  a  form  of  the 
better-known  Equisetum  icevigatum.  Whether  this  is 
true  or  not  will  necessitate  further  study  of  both  plants 
in  the  field.  Should  it  be  proved  to  be  a  form  of  Equi- 
setum Icevigatum,  it  would  be  known  as  Equisetum 
Icevigatum  Funstoni,  since  the  other  was  first  named. 

The  new  stems  of  the  branched  scouring-rush  make 
their  appearance  early  in  the  year,  and  by  the  middle  of 
March    are    in    fruit.     At    maturity    they    may    reach   a 


BRANCHED  EQUISETUM       l-.qit/sc/um  Fuusfoui. 


THE  SCOURING-RUSHES. 


35 


height  of  two  feet  or  more,  with  a  diameter  of  a  quarter 
of  an  inch.  They  contain  from  ten  to  thirty  grooves, 
the  ridges  somewhat  rounded  and  usually  rough  with 
many  cross-bands  of  silex.  The  sheaths  are  twice  as 
long  as  they  are  wide,  and  are  tipped  with  triangular, 
long-pointed  teeth,  most  of  which  are  torn  off  by  the 
developing  stems,  the  rest  falling  at  maturity.  The 
teeth  are  dark  brown  or  black  with  a  pale  margin,  and 
the  bases,  which  remain  attached  to  the  sheaths,  are 
slightly  grooved  in  the  centre.  Each  leaf  has  a  low 
ridge  extending  lengthwise,  and  the  upper  margin,  where 
it  is  separated  from  the  others,  is  slightly  raised.  In 
cross-section  more  than  four  fifths  of  the  stem  is  hollow, 
and  both  the  carinal  and  vallecular  canals  are  very  small, 
or,  occasionally,  wanting. 

Much  remains  to  be  observed  regarding  the 
development  and  duration  of  the  stems  of  this 
species.  Apparently  the  erect  fruiting  stems 
do  not  branch,  at  least  not  until  after  fruiting, 
but  the  sterile  stems  produce  regular  whorls 
of  branches  as  they  develop.  There  is  also 
a  form  of  the  sterile  stem,  most  noticeable  in 
winter,  which  spreads  flat  on  the  ground  and 
sends  out  a  multitude  of  short,  very  slender 
branches  from  the  base,  forming  dense  mats. 
In  this  form  the  stems  are  about  ten-angled, 
and  the  teeth  are  silvery  white  and  persistent. 
It  does  not  seem  to  be  known  whether  the 
fertile  and  sterile  stems  last  through  the  win- 
ter, but,  reasoning  from  the  analogy  of  related 
species,  it  may  be  assumed  that  they  do. 

The  fruiting-catkins  are  among  the  largest  produced  by 
this  group  of  plants,  being  about    three  quarters  of  an 


Catkin  of 
Equiseiuvi 


% 


'unstont. 


36  THE  SCOURING-RUSHES. 

inch  long  and  a  third  as  broad.  They  are  nearly  ovate, 
with  a  rounded  apex,  and  the  base  is  either  included  in 
the  uppermost  sheath  or  raised  above  it  on  a  short  stem. 
In  most  specimens  there  is  a  cup-shaped  sheath  of  the 
same  colour  as  the  catkin,  closely  appressed  to  the  lowest 
whorl  of  sporophylls. 

Equisetum  Funstoni  is  a  plant  of  the  extreme  South- 
west. It  is  very  abundant  in  southern  California  below 
about  1,500  feet  altitude,  and  prefers  moist  sand,  espe- 
cially along  streams,  although  it  occasionally  grows  in 
soil  so  dry  that  the  stems  perish  during  the  summer.  In 
general  appearance  the  species  is  so  much  like  Equisetum 
IcBvigatum  that  it  is  easily  mistaken  for  it.  Four  ecologi- 
cal forms  have  been  named.  It  is  interesting  in  this 
connection  to  note  that  there  are  but  two  other  species 
of  Equisetum  in  the  world,  named  for  botanists. 

The  Variegated  Scouring-Rush. 

One  familiar  with  the  appearance  of  the  smooth 
scouring-rush  might  easily  mistake  the  variegated 
scouring-rush  {^Equisetum  variegatuui)  for  a  small 
form  of  that  species.  Superficially  they  are  much 
alike  except  in  size  and  the  markings  of  the 
sheaths,  but  a  close  examination  will  show  many 
other  points  of  difference.  Equisetum  variega- 
tum  is  much  the  more  widely  distributed,  and 
in  America  the  habitats  of  the  two  do  not 
overlap  to  any  great  extent. 

The  stems    of  this  species  grow   in   tufts   from 
the  apex  of  the  rootstock,  and  reach  a  height  of 
Sheath  of     from  six  to   twenty  inches.     They  are  slender, 
varYega7iZt.  barely  an  eighth  of  an  inch  in  diameter,  and  so 


VARIEGATED  SCOURING-RUSH.      Equisetiim  ^uiriegaium. 


THE  SCOURING-RUSHES.  37 

weak  that  they  often  spread  about  in  a  half-recumbent 
position.  Externally  they  are  marked  with  from  four  to 
ten  broad,  rounded,  or  slightly  two-angled  ridges  with 
still  broader  hollows  between.  A  cross-section  shows  the 
central  hollow  to  be  about  one  third  the  total  diameter, 
the  vallecular  canals  to  be  relatively  large  and  trans- 
versely oval,  while  the  carinal  canals  are  much  smaller. 

The  sheaths  are  of  moderate  length,  slightly  dilated 
upward,  and  tipped  with  elongated,  triangular,  slender- 
pointed  teeth  with  white  margins  which  may  or  may  not 
fall  off  at  maturity.  At  the  base  of  old  stems  the  sheaths 
are  jet  black;  higher  up  they  are  ash-colour  with  two 
black  girdles,  one  at  the  base  and  one  on  the  margin; 
while  near  the  apex  and  in  young  stems  they  may 
be  clear  green  with  only  a  narrow  blackish  band 
on  the  margin.  The  leaves  are  four-ridged,  the 
two  middle  ridges  separated  by  a  rather  deep 
groove,  this  latter  being  considered  an  impor- 
tant point  in  identifying  the  species.  The  cat- 
kins are  slightly  ovate,  half  an  inch  or  under 
in  length,  and  tipped  with  a  comparatively  large 
point.  After  fruiting,  the  sporophylls  often  fall 
from  the  axis  of  the  cone,  which  may  persist  in 
this  condition  for  some  time. 

The  variegated  scouring-rush  is  a  lover  of  the 
North,  and  inhabits  a  zone  encircling  the  earth  Eg^'^l^tum 
from  about  the  42d  parallel  of  north  latitude  to  ^'^^"^^"'^'"" 
the  Arctic  Circle  and  beyond.  In  the  southern  part  of 
its  American  range  it  has  been  reported  from  all  the 
northern  tier  of  States  and  from  Illinois  and  Indiana. 
It  has  often  been  reported  from  the  Southwestern 
States,  but  it  is  likely  that  in  such  cases  EqiiisetiiDi. 
licvigatum  may  have  been   mistaken   for  it.      It  grows  in 


38  THE  SCOURING-RUSHES. 

swamps,  on  wet  rocks,  and  on  the  gravelly  borders  of 
streams,  but,  according  to  Eaton,  seldom  in  sand.  In 
Europe  it  has  been  reported  as  occurring  in  sandy  places 
near  the  seashore.  In  the  northern  part  of  its  range  the 
stems  possibly  do  not  survive  the  win- 
ter, but  farther  south  there  is  evidence 
that  a  majority,  if  not  all,  are  evergreen. 
The  specific  name,  variegatum,  refers 
to  the  appearance  given  to  the  stem 
by  the  black  sheaths.  Four  varieties 
Cross  Section  of  Stem,  have  bccu  named,  of  which  Alaskamirn, 
found  from  the  State  of  Wasliington  northward,  is  the 
most  noteworthy.  It  is  regarded  by  many  as  being  a 
connecting  link  between  this  species  and  Eqiiisetuni  Jiie- 
inale, 

T'he  Dwarf  Scouring-Rush. 

After  puzzling  over  the  minute  differences  that  are 
often  depended  upon  for  separating  the  other  species  of 
Equisetttni,  it  is  refreshing  to  turn  to  one  like  the  dwarf 
scouring-rush  {Equisetiim  scirpoides)  that  is  so  distinct 
in  form  and  so  characteristic  in  appearance  that  even  the 
beginner,  finding  it  for  the  first  time,  has  no  doubt  as  to  its 
identity.  It  is  the  smallest  living  species  of  Equisetuvi^ 
and  for  this  reason  is  often  overlooked  in  regions  where 
it  is  fairly  common. 

This  species,  though  growing  only  in  the  colder  parts 
of  America,  is  an  evergreen,  and,  like  its  relative,  the 
common  scouring-rush,  carries  many  of  its  fruit-buds 
through  the  winter.  Almost  as  soon  as  the  snow  has  dis- 
appeared,  the  first  catkins  begin  discharging  their  spores, 
and  the  plant   continues  to    fruit  through  the  summer. 


DWARF  SCOURING-RUSH.      Equisetum   scirpoidcs. 


THE  SCOURING-RUSHES.  39 

The  greatest  number  of  mature  spikes  will  probably  be 
found  about  the  middle  of  April,  making  it  one  of  the 
earliest  fruiting  species  of  Eqtiisetiun. 

The  stems  grow  in  dense  tufts,  the  longest  barely 
reaching  a  height  of  ten  inches,  and  are  so  slender  as  to 
be  almost  threadlike.  They  are  often  branched 
at  base,  but  seldom  so  above,  unless  they  become 
prostrate  and  covered  with  soil.  The  fertile  stems 
are  nearly  erect,  but  the  sterile  are  flexuous  and 
bend  over  at  the  tip.  When  dried  for  the  herba- 
rium they  often  coil  into  circles  or  even  double 
circles.  The  stem  is  six-angled,  but  there  are 
only  three  leaves  in  the  sheath.  In  all  other 
species  of  Equisetum  the  number  of  leaves  in  the 
sheath  and  the  number  of  angles  in  the  stem  are 
equal,  and  the  apparent  anomaly  presented  by 
this  species  is  explained  by  the  fact  that  in  addi- 
tion to  the  true  ridges  there  is  an  equal  number 
of  false  ridges  over  the  vallecular  canals.  The^"^^^^" 
three  leaves  are  not  joined  together,  and  do  not  prop- 
erly form  a  sheath,  in  this  showing  very  clearly  that  the 
sheaths  of  the  other  species  are  formed  of  confluent 
leaves.  The  teeth  are  small,  slender,  black,  with  pale 
margins,  and  are  not  deciduous.  The  leaves  have  one 
deep  central  groove  and  two  lighter  lateral  ones,  making 
them  four-keeled.  In  age,  both  leaves  and  sheaths  be- 
come dark  brown  or  black.  Unlike  all  other  equisetums, 
the  stems  of  this  species  have  no  central  hollow.  The 
vallecular  canals  are  comparatively  large,  and  the  carinal, 
though  small,  are  present. 

The  fruiting-spikes  are  scarcely  larger  than  pepper- 
corns and  consist  of  about  half  a  dozen  small  sporophylls 
on  an  axis  tipped  with  a  tiny  black  point.     Many  of  the 


40 


THE  SCOURING-RUSHHS. 


embryo  fruit-spikes  seem  never  to  become  fully  developed. 

The  first  spores  are  ripe  at  about  the  time  the  anemone 

and  spring  beauty  are  blooming. 

The  dwarf  scouring  -  rush  is  found  from 
Greenland  and  Alaska  south  to  Pennsylvania, 
Illinois,  Nebraska,  Montana,  and  British  Co- 
lumbia. It  is  also  found  in  northern  Europe 
and  Asia.  The  stations  on  the  southern  limits 
of  its  range  in  America  are  widely  separated, 
and  the  plant  does  not  begin  to  become 
common  until  the  northern  boundary  of  the 
United  States  is  reached. 

A  writer  in  the  Fern  Bulletin  reports  it  as 
covering  several  acres  in  western  Connecticut, 
and  says  of  its  habitat : 


CATKIN. 


"  It  seems  to  favour  moist,  thickly  wooded  hillsides 
for  the  place  of  its  ahode,  although  Mr.  Grout  found 
it  in  a  cold  boggy  meadow.  The  place  where  I  first  saw  this  plant 
is  a  steep  hillside  thickly  grown  up  to  hemlock  and  white  pine. 
Underneath,  the  little  Taxus,  or  ground  hemlock,  grows  in  abun- 
dance, and  the  twisted-stalk,  showy  orchis,  red  trillium,  and  round- 
leaved  violet  are  its  companions." 

It  is  also  found  on  wooded  banks,  decayed  logs,  and 
among  fine  grasses,  usually  in  forest  regions.  Since  it  so 
nearly  resembles  the  grasses  and  sedges  among  which  it 
grows,  the  best  time  to  search  for  it  is  early  in  the  year, 
before  the  other  early  vegetation  has  started  up. 


THE  DECIDUOUS  EQUISETUMS, 
OR  HORSETAILS. 


THE  HORSETAILS. 


HE  separation  of  the  Equisetaceae  into 
two  divisions,  called  respectively  the 
Scourin^^-Rushes  and  the  Horsetails,  is 
at  best  but  an  arbitrary  classification. 
The  manner  of  growth,  the  structure 
of  the  stem,  and  the  method  of  fruit- 
ing are  the  same  in  all,  and  they  are 
therefore  properly  placed  in  a  single  genus.  There  are 
however,  certain  very  noticeable  characters  by  which 
even  the  novice  may  separate  them  into  the  groups 
mentioned,  and  in  the  popular  mind  they  are  usually  so 
separated.  As  treated  in  this  book,  the  horsetails  will 
be  considered  as  those  species  of  Eqiiisetiim  in  which 
the  stems  die  at  the  approach  of  winter  and  the  fruiting- 
cones  are  without  a  terminal  point.  Their  sterile  stems 
also  usually  produce  regular  whorls  of  branches,  add  the 
fertile  often  do  so.  These  form  the  section  Eticquisetuni, 
or  Eguisetum  proper,  of  the  systematist. 


The   Field  Horsetail. 


The  field  horsetail  {Eqtiisetuin  arvense)  is  without 
doubt  the  most  abundant  species  of  Eqiiiscttini  in  the 
world.  Not  only  is  it  widely  distributed,  but  wherever 
it  grows  it  usually  occurs  in  the  greatest  abundance- 
Normally  a   moisture-loving  plant,  it   can  adapt  itself  to 


44  THE  HORSETAILS. 

a  wide  variety  of  situations,  and  is  often  found  in  dry 
and  sterile  places  in  which  few  other  plants  can  exist, 
such  as  dry  roadsides  and  railway  embankments.  In 
the  latter  situation  it  thrives  exceedingly  well,  and, 
though  rooted  in  cinders,  covers  vast  stretches  of  the 
surface  with  a  pleasing  mat  of  its  yellowish-green  sterile 
stems.  All  who  have  ever  travelled  a  dozen  miles  on  a 
railway  in  summer  have  doubtless  seen  this  plant. 

The  appearance  of  the  fertile  stems  of  this  species  is 
among  the  first  signs  of  returning  spring.  They  come 
almost  before  the  grass  has  begun  to  green,  often  start- 
ing up  in  such  numbers  as  to  give  a  strong  tinge  of  their 
own  warm  flesh-colour  to  the  sunny  slopes  on  -which 
they  grow.  There  is  something  very  mushroom-like  in 
the  rapidity  with  which  these  fleshy  stems  mature  when 
once  they  have  started  to  develop,  and  the  likeness  is 
increased  by  the  fact  that,  like  the  mushroom,  they  have 
no  green  in  their  composition. 

The  first  stems  are  usually  fully  developed  and  show- 
ing their  spores  long  before  one  has  discovered  that  they 
have  started.  If  one  begins  the  season  early  enough, 
however,  he  may  find  just  beneath  the  surface  of  the 
earth  numerous  buds  in  which  the  fruiting-cones  are  all 
complete  and  waiting  for  the  first  warm  day  to  call  them 
forth.  Indeed,  as  early  as  midsummer  of  the  preceding 
year  these  buds  inay  be  found.  Just  before  growth 
commences  they  often  measure  an  inch  or  more  in 
length  and  half  an  inch  in  diameter.  At  this  time  the 
sheaths  are  also  fully  developed,  and  overlap  one  another 
like  shingles  on  a  roof,  thus  completely  enclosing  the 
catkin.  Growth  consists  in  the  development  of  the 
internodes,  and  often  proceeds  at  the  rate  of  nearly  two 
inches  a  day.     At   maturity  they  are  from  a   few  inches 


,:^-  ^1 


FIELD  HORSETAIL.     Eqidsctum  arvensc. 
Sterile  frond. 


FIELD  HORSETAIL.     Equisctiun  arvense. 
Fertile  frond. 


THE  HORSETAILS.  45 

to  a   foot  or  more   high,  but   less   than  a   quarter  of  an. 
inch  in  diameter      The  earliest  stems  are  to  be  found  in 
dry  sandy  places  ;    those   growing   in  wet  or  clay  soils 
develop  much  later. 

The  full-grown  fertile  stems  are  most  attractive  objects, 
the  yellowish  sheaths  with  long,  pointed,  dark-brown  teeth 
contrasting  very  prettily  with  the  deep  flesh-colour  of 
the  internodes.  There  are  usually  from  six  to  ten  of 
these  sheaths  on  a  stem,  each  nearly  an  inch  in  length 
and  half  an  inch  wide,  at  the  top,  flaring  upward  like  a 
funnel.  The  upper  sheaths  are  usually  largest.  In  the 
bud,  the  bases  of  these  sheaths  are  deep  yellow  in  colour. 

The  mature  cones  are  yellowish-brown  and  frequently 
two  inches  in  length.  They  are  a  third  of  an  inch  in 
diameter  and  much  like  those  of  the  scouring-rush  in 
appearance,  except  that  they  are  softer  and  more  catkin- 
like and  lack  the  hard  terminal  point.  The  sporophylls, 
owing  to  the  way  they  are  placed  in  the  cone,  are  usually 
six-sided,  but  there  are  often  more  than  six  sporangia, 
and  the  outer  ends  of  these  are  plainly  indicated  by 
elevations  on  the  outer  surface  of  the  sporophylls.  The 
spores  are  produced  in  great  abundance,  and  at  the 
proper  time  the  slightest  jar  will  suffice  to  shake  them 
out  in  grey-green  clouds.  By  striking  a  ripe  cone  upon 
the  back  of  the  hand  one  may  shake  out  a  little  heap  of 
spores  that  under  a  simple  lens  may  be  seen  suddenly  to 
boil  up,  at  the  same  time  becoming  lighter  in  colour. 
This  is  due  to  the  uncoiling  of  the  elaters  as  the  mois- 
ture in  them  evaporates  and  the  spores  prepare  to  drift 
away  on  the  wind. 

Soon  after  the  spores  have  been  shed,  the  fertile  stems 
wither  and  disappear.  At  the  same  time  the  sterile 
fronds    begin    to    be  noticed,  springing    from  the  small 


46  THE  HORSETAILS. 

buds  at  the  top  of  the  rootstock  near  the  point  where 
tlie  fertile  stem  arises.  Tlie  sterile  stems  are  much 
taller  than  the  fertile,  in  favourable  circumstances  reach- 
ing a  height  of  three  feet.  Ordinarily  they  are  from  ten 
to  fifteen  inches  high.  The  sheaths  are  shorter  and  nar- 
rower than  those  of  the  fertile  stems,  but,  like  them,  are 
dilated  upward.  They  are  never  so  noticeable,  being 
usually  pale  green  in  colour  and  tipped  with  slender 
dark-brown  teeth.  Toward  the  base  of  the  stem  the 
entire  sheath  may  be  dark  brown. 

In  the  section  to  which  the  field  horsetail  belongs,  the 

structure  and   number  of  grooves   in  the  stem  and  the 

arrangement  of  the  sheaths  play  a  less  important  part-  in 

the    identification    of    the  species    than   they  do  in    the 

HippocJicete.     They   are,   however,  not 

without  value  for  this  purpose.     In  the 

present  species   it    may   be  noted   that 

there  are   eight  or  more  leaves   in   the 

sheath   of  the   fertile  stem,   and  about 

fifteen  in  that  of  the  sterile  one.     Since 

there  is  usually  one  leaf  for  each  groove 

Section  of  stem.         ^^  ^j^^  ^^^^^^^  ^j^^  number  of   the    latter 

is  easily  ascertained.  The  tips  of  the  leaves  of  this 
species  are  not  deciduous,  and  the  central  hollow  of  the 
stem  occupies  about  one  third  of  its  diameter. 

In  what  may  be  considered  the  normal  plant,  the  stem 
is  erect  and  bears  about  twenty  whorls  of  slender 
branches,  a  whorl  at  each  joint  of  the  stem.  Each  whorl 
consists  of  a  dozen  or  more  simple,  three-angled,  ascend- 
ing branches  six  inches  or  more  long,  making  a  bushy 
frond  in  which  it  is  not  difficult  to  fancy  a  likeness  to 
the  tail  of  a  horse.  Doubtless  it  was  the  appearance  of 
this    species    that    earned    the    common    name    for   the 


/ 

J^^^^^^!y^W\>>*" 

:^ 

M 

^M'. 

i 
i 

1 

i      ^-' 

■  M' 

P 

r; 

•     ^ 

* 

^ 

PLATE   II.    WOOD    HORSETAIL.      Equisetian  silvaticum. 

COPYRIGHT,    1905,    BY    FFECERICK    A      STOKES   COWPANV 


THE  HORSETAILS.  47 

group.  The  branches,  as  in  the  evergreen  species,  are 
produced  from  buds  in  the  axils  of  the  leaves  in  the 
sheath,  and  these,  as  they  develop,  burst  through  the 
base  of  the  sheath  instead  of  growing  up  out  of  it. 
The  branches  are,  of  course,  jointed  like  the  stems,  with 
sheaths  at  the  joints,  and  at  their  junction  with  the  main 
stem  each  is  surrounded  with  a  dark-coloured  sheath  of 
its  own  which  gives  an  additional  girdle  of  colour  to  the 
joints  of  the  main  stem.  In  the  ordinary  plant  a  few  of 
the  lower  nodes  do  not  produce  branches,  while  toward 
the  tip  the  whorls  of  branches  are  successively  shorter, 
forming  a  blunt-ended  frond  above  which  the  stem  con- 
tinues for  a  short  distance  as  a  slender  prolongation. 

As  might  be  expected  of  a  plant  growing  under  such 
diverse  conditions  of  light,  warmth,  and  moisture,  there 
is  great  variation  in  the  form  of  the  sterile  frond.  Mr. 
A.  A.  Eaton  has  recorded  no  less  than  nine  named  forms 
in  the  Fern  Btilletin.  None  of  these  seem  fixed,  and 
it  is  likely  that  all  can  be  changed  to  the  normal  form  by 
a  change  in  the  soil  or  surroundings.  The  erect  form 
which  we  have  taken  as  typical  is  mainly  found  in  moist, 
rich,  light  soil  in  half  shade.  The  next  most  noticeable 
form  is  named  deciunbcns,  and  is  characterized  by  the 
main  stem  spreading  along  the  ground  with  only  the  tip 
erect.  The  short  branches,  however,  are  all  erect,  and 
this  makes  a  peculiar  one-sided  form  easy  to  recognize. 
It  is  common  in  exposed  sterile  soil  and  is  usually  to  be 
found  on  railway  embankments.  In  the  form  called 
diffusinn  there  appears  to  be  no  central  stem,  the 
branches  arising  from  the  summit  of  the  rootstock  and 
spreading  flat  on  the  earth.  This  is  often  found  along 
roadsides,  and  in  other  places,  in  the  company  of  deciim- 
bens.     Pseudosylvatic2iin  is  a  form  in  which  the  branches 


4S  THE  HORSETAILS. 

branch  again,  as  they  do  in  the  wood  horsetail.  In 
these  forms  the  branches  have  no  central  hollow,  and 
many  of  them  are  more  than  three-angled. 

The  fertile  fronds  seem  little  inclined  to  change  with 
the  changes  of  the  sterile  one.  Occasionally,  however, 
small  catkins  appear  on  the  tips  of  sterile  stems  in 
early  summer,  forming  the  variety  cauipcstre.  This  is 
supposed  to  be  due  to  a  late  spring  frost  cutting  down 
the  regular  fertile  fronds,  and  thus  throwing  a  fruiting 
tendency  into  the  sterile  stems. 

The  main  rootstock  of  this  species  is  perennial, 
branching,  and  creeps  extensively  a  foot  or  more  below 
the  surface  of  the  earth.  At  short  intervals  secondary 
rootstocks  are  given  off,  and  these  go  directly  to  the 
surface,  there  giving  rise  to  both  fertile  and  sterile  fronds. 
The  rootstocks  are  in  all  respects  like  the  stems  except 
that  they  lack  the  central  hollow.  The  internodes  of  the 
secondary  rootstocks  are  often  heavily  clothed  with  short, 
tawny  felt,  and  at  the  nodes,  as  in  the  main  rootstock, 
the  usual  sheaths  occur.  From  the  base  of  the  buds  in  the 
axils  of  these  sheaths  the  roots  are  produced.  When  the 
buds  develop  they  produce  rootstocks,  though  if  exposed 
to  the  air  they  may  take  on  the  form  and  function  of  stems. 
They  often  remain  dormant  for  an  indefinite  period,  but 
will  grow  at  once  if  needed  in  the  economy  of  the  plant. 

The  secondary  rootstocks  often  bear  at  the  nodes 
small  rounded  tubers  as  large  as  peas.  These  have  the 
same  structure  as  the  rootstock,  and  are  probably  in  the 
nature  of  arrested  branches.  More  than  a  dozen  of 
these  tubers  have  been  found  on  a  twelve-inch  section 
of  secondary  rootstock.  It  has  been  conjectured  that 
these  tubers  act  as  storehouses  of  food  upon  which  the 
plant  can  draw  when  the  fronds  are  developing. 


Equiscttini  iwi'ense  dectinibens. 


V     ^ 


Equisetiun  arvense  campesire. 


THE  HORSETAILS. 


49 


In  Great  Britain  this  species  is  called  "  corn  horsetail," 


J 


C^' 


J\ 


/i 


^A 


m 


1^ 


a  great  many  names  referring  to  its  appear- 
ance, among  which  may  be  me4itioned 
"  mare's- tail  ,"  "  cat's  -  tail ,"  "  colt's-tail,  " 
"fox -tail,"  "pine -top,"  "  pine -grass,  " 
"  meadow -pine,  "  and  "  bottle- brush." 
"  Jointed  rush,"  in  allusion  to  its  structure, 
and  "  snake-grass,"  a  reference  to  its  habitat, 
are  names  it  shares  with  other  species  of 
Eqiiisetiun.  In  old  botanical  works  it  is 
occasionally  called  "  toad-pipes,"  "  paddock- 
pipes,"  and  "  tad-pipes,"  all  of  which  have 
been  given  in  reference  to  its  association 
with  frogs  and  toads,  "  paddock "  being 
an  old  word  for  "  frog."  The  appellation 
"  smoke-rush  "  is  not  clear. 

The  field  horsetail  is  found  around  the 
world  in  the  northern  hemisphere  from  lati- 
tude 38°  to  83°.  It  has  also  been  reported 
from  the  Canaries  and  from  the  Cape  of 
Good  Hope.  In  the  United  States  it  does 
not  appear  to  reach  the  Gulf  States,  but  it 
is  found  sparingly  in  California.  It  grows 
in  woods,  fields,  meadows,  swamps,  and 
along  streams,  and  is  especially  plentiful 
along   railways.      When  fresh,  cattle  eat  it 


\^h. 


^  s  ^ 

BUDS  AND  TUBERS  OF  FIELD  HORSETAIL. 


50  THE  HORSETAILS. 

with  impunit}',  though,  when  cut  witli  tlie  hay  it  has 
been  found  to  be  quite  poisonous  to  horses.  At  the 
first  hard  frost  in  autumn,  the  stems  in  exposed  places 
perish,  but  where  protected  by  vegetation  they  may 
exist  for  some  time  longer. 

•  This  species  is  so  widely  distributed  that  the  cultiva- 
tor of  the  fern  allies  seldom  has  to  transplant  it  to  his 
grounds  ;  but  if  it  be  desired  to  make  it  grow,  nothing  is 
easier.  A  bit  of  the  root-stock,  planted  almost  any- 
where, will  soon  produce  one  of  its  characteristic  thickets. 
Once  started,  it  is  most  tenacious  of  life,  and  if  buried 
six  feet  or  more  in  loose  soil  will  ultimately  come  to  the 
surface  a^rain. 


'The  Ivory   Horsetail. 


It  is  a  curious  coincidence  that  the  commonest  species 
in  both  groups  of  Eqtiisetiim  should  each  be  related  to  a 
second  species  that  very  much  resembles  it  except  in 
size.  The  great  scouring-rush  is  so  near  like  the  com- 
mon one  that  it  may  be  doubted  whether  the  two  are 
not  forms  of  a  single  species ;  but  in  the  case  of  the 
field,  horsetail  and  its  gigantic  counterpart  no  such 
uncertainty  exists.  The  difference  in  size  alone  would 
almost  be  sufficient  to  distinguish  them,  for  the  sterile 
fronds  of  this  giant  species,  the  ivory  horsetail  (i^^/^?>r///w 
tchnateid),  often  reach  a  height  of  ten  feet.  Otherwise 
the  two  have  many  points  of  general  resemblance,  though 
none  are  sufficiently  close  to  cause  confusion  in  identify- 
ing them.  Both  are  among  the  earliest  of  spring  plants 
and  are  able  to  grow  in  a  variety  of  situations,  and  the 
fertile  fronds  are  sharply  differentiated  from  the  sterile, 
dying  soon  after  the  spores  are   shed.     In  view  of  these 


IVORY  HORSETAIL.     Eqit/sc/it/n  tdmatcia. 
Fertile  frond. 


THE  HORSETAILS.  51 

resemblances  it  is  curious  that  the  range  of  Eqiiisctitvi 
tciuiateia  in  America  should  be  restricted  to  a  narrow 
strip  of  country  on  the  Pacific  coast,  while  Eqiiisetum 
arvciise  is  spread  over  nearly  the  whole  continent.  The 
two  may  thus  sometimes  grow  in  the  same  locality,  but 
no  intergrading  forms  have  been  found.  When  they  grow 
in  company,  Eqiiisetnui  arvense  appears  to  be  a  week  or 
more  earlier  than  Eqiiisetiim  telmatcia.  The  time  at  which 
the  fertile  spikes  appear  depends  somewhat  on  the  locality. 
In  California,  according  to  Campbell,  growth  continues  all 
winter,  and  the  fertile  fronds,  developing  gradually, 
spring  up  and  spread  their  spores  whenever  they  are  ripe. 

In  British  Columbia  the  fertile  spikes  are  produced 
during  the  first  warm  days  of  spring,  which  occur  about 
the  middle  of  April.  In  a  short  time  they  have  reached 
a  height  of  from  ten  inches  to  two  feet,  with  a  diameter 
of  an  inch  or  more.  The  stems  are  therefore  the  heavi- 
est of  any  species  in  the  North  Temperate  Zone.  They 
are  reddish  brown,  contain  thirty  or  more  shallow 
grooves,  and  at  the  joints  are  encircled  by  the  large, 
loose,  light-brown  sheaths,  which,  including  the  long, 
slender  teeth,  are  nearly  two  inches  in  length.  The  cat- 
kins are  two  or  three  inches  long,  and  three  quarters  of 
an  inch  thick,  and  consist  of  twenty  or  thirty  whorls  of 
sporophylls. 

The  sterile  fronds  appear  as  the  spores  are  being  shed. 
These  are  ordinarily  about  three  feet  high,  though  in 
favourable  situations  they  may  attain  to  more  than 
thrice  that  height,  in  such  cases  being  half  supported  by 
the  shrubbery  among  which  they  grow.  Often  they 
grow  in  such  masses  that  it  is  difficult  to  pass  through 
them.  When  the  stems  appear,  the  branches  are  short 
and  closely  appressed,  but  later  they  spread   out   some- 


52  THE  HORSETAILS. 

what,  as  In  the  field  horsetail.  There  are  sometimes 
more  than  twenty  whorls  of  these  branches,  and  from 
twenty  to  forty  branches  in  a  whorl.  Near  the  tip  the 
whorls  are  rather  close  together  ;  below,  they  are  farther 
apart,  and  the  lower  third  of  the  stem  is  naked.  The 
average  length  of  the  branches  is  nearly  six  inches,  but 
in  some  instances  they  are  three  times  as  long.  The 
sterile  stems  are  pure  white,  and  the  sheaths  which 
closely  invest  them  are  pale  green,  with  brown  teeth. 
The  common  name  of  this  species  was  given  in  allusion 
to  the  colour  of  these  stems. 

Although  the  ivory  horsetail  grows  in  regions  where 
the  earth  is  not  penetrated  very  deeply  by  the  frost,  in 
the  North,  at  least,  its  stems  are  strictly  annual.  The 
rootstock  is  similar  to  that  of  Eqiiisctitm  arvcnse,  though 
larger,  and  at  the  nodes  it  also  bears  numerous  tubers 
which  are  as  large  as  marbles.  These  tubers  often  occur 
in  necklace-like  strings,  and  show  very  plainly  that  they 
are  the  swollen  internodes  of  the  rhizome. 

Like  Equischiiii  arvense,  this  species  has  numerous  vari- 
eties, mostly  of  an  ecological  nature.  Late  in  the  year 
one  may  find  fruiting-cones  on  the  ordinary  green  stems. 
In  the  case  of  similar  cones  on  the  normally  sterile 
fronds  of  Equisetum  arvense^  it  has  been  assumed  that 
they  have  been  caused  by  an  injury  to  the  fertile  stems; 
but  in  Francis's  ''  British  Ferns  "  it  is  stated  that  the 
cones  on  Equisetum  telinateia  are  caused  by  drought,  and 
that  with  specimens  grown  in  pots  these  cones  may  be 
produced  at  will  by  withholding  water  at  the  proper 
time. 

Equisetum  telmateia  is  well  distributed  in  the  Old 
World,  being  found  from  Ireland  and  Scotland  to 
Siberia,    Persia,  and    North   Africa.     In    America    it    is 


IVORY  HORSETAIL.     iLqniscium  telmateia. 
Section  of  Sterile  frond. 


THE  HORSETAILS.  53 

found  at  low  altitudes  along  the  coast  from  southern 
California  to  British  Columbia  and  Alaska,  being  abun- 
dant in  the  central  part  of  its  range  and  the  dominant 
Eqiiisettim  in  British  Columbia.  According  to  Mr.  A.  J. 
Mill,  the  Indians  are  said  to  eat  the  fertile  spikes.  In 
addition  to  the  usual  common  names,  this  plant  is  some- 
times called  the  "  great  water  horsetail  "  and  the  *'  mud 
horsetail,"  neither  of  which  is  very  appropriate,  at  least 
in  this  country,  where  the  plant  grows  in  any  soil,  includ- 
ing railway  embankments.  The  spores  lose  their  vitality 
soon  after  they  are  shed,  and  this  may  perhaps  account 
for  its  being  less  abundant  than  the  field  horsetail.  The 
species  seems  to  be  rarely  cultivated,  though  it  ought  to 
be  a  most  desirable  species  for  decorative  planting. 

The   Shade   Horsetail. 

The  American  collector  is  likely  to  see  little  of  the 
shade  horsetail  {Eqiiisetiim  pratensc),  for  its  centre  of 
distribution  is  in  the  far  North.  Only  a  few  stations  for 
it  in  the  United  States  are  known.  It  is  possible,  how- 
ever, that  when  students  become  more  familiar  with  this 
species  it  will  be  found  to  be  more  widely  distributed. 
Its  rather  close  resemblance  to  the  field  horsetail  makes 
it  easily  overlooked  by  the  novice. 

One  of  the  important  features  in  which  this  species 
differs  from  the  field  horsetail  is  found  in  the  fertile 
shoots,  which,  after  the  spores  have  been  shed,  put  forth 
whorls  of  branches  from  the  nodes  and  thereafter  behave 
in  all  respects  like  sterile  stems.  While  this  is  true  of 
the  majority,  other  stems  may  be  found  that  die  as  soon 
as  the  spores  are  shed,  and  the  species  is  therefore 
usually  described  as -having  three  kinds  of   fronds.     The 


54  THE  HORSETAILS. 

vegetative  impulse  seems  to  exist  in  different  proportions 
in  each  one,  some  having  so  Httle  that  they  do  not  sur- 
vive the  spring  fruiting.  It  is  interesting  to  know  that 
the  size  of  the  sheaths  varies  with  the  kind  of  stem, 
being  largest  in  the  evanescent  fertile  stems,  of  medium 
size  in  those  fruiting  stems  that  later  bear  branches,  and 
smallest  in  the  wholly  sterile  ones.  Before  the  fertile 
stems  have  produced  branches,  they  are  much  like  the 
fertile  stems  of  the  field  horsetail,  except  that  they  are 
usually  shorter,  slenderer,  paler  in  colour,  and  with  less 
flaring  sheaths.  They  have  been  described  as  sea  green 
with  pale  sheaths  tipped  with  long,  pointed,  white- 
margined  brown  teeth.  The  catkins  are  about  cylin- 
drical, an  inch  long,  and  a  quarter  as  wide,  and  perish  as 
soon  as  the  spores  are  shed. 

The  sterile  stems  are  erect,  fifteen  inches  to  two  feet 
in  height  and  very  slender.  They  are  white  or  pale 
green  in  colour  and  contain  from  eight  to  twenty  grooves. 
Below,  the  stems  are  smooth,  but  toward  the  apex  the 
ridges  are  thickly  set  with  tooth-like  projections  of  silex 
which  are  frequently  large  enough  to  be  seen  with  the 
unaided  eye.  The  sheaths  closely  encircle  the  stem, 
and  are  pale  green,  tipped  with  white-margined  brown 
teeth  similar  to  those  of  the  fertile  stems.  In  the  upper 
two  thirds  of  the  frond,  each  node  gives  rise  .to  a  whorl 
of  simple,  jointed,  three  or  more -angled  branches. 
These  are  peculiar  for  having  the  joint  nearest  the  stem 
short  and  bent  sharply  downward,  while  the  rest  of  the 
branch  is  spreading  or  ascending.  This  character  is  one 
that  the  eye  readily  appreciates. 

The  shade  horsetail  is  found  in  the  North  Temperate 
and  Arctic  Zones  of  both  hemispheres.  Accordin'g  to  A. 
A.  Eaton  it  ranges  southward   to  New  Jersey,  Michigan, 


SHADE  HORSETAIL.     Eqiiisetum pratense. 
Sterile  frond. 


SHADE  HORSETAIL.     Eqinsetuvi pratense. 
Fertile  frond. 


THE  HORSETAILS.  55 

Minnesota,  and  alon^^  the  Rocky  Mountains  to  Colorado. 
It  has  also  been  reported  from  Iowa.  In  Minnesota  it 
is  said  to  be  common,  but  elsewhere  in  the  United 
States  it  is  very  rare.  From  Alaska  to  the  Hudson 
Bay  region  it  appears  to  be  plentiful.  It  is  more  abun- 
dant in  the  Old  World  than  with  us,  growing  in  culti- 
vated fields  as  well  as  in  waste  places,  often  so  plentifully 
as  to  be  considered  a  troublesome  weed.  Eaton 
observes  that  it  must  be  common  in  the  rye  fields  of 
Germany,  since  it  is  nearly  always  present  in  the  straw 
in  which  German  glass  is  packed  for  export. 

In  appearance  and  habitat  this  species  stands  so 
nearly  midw^ay  between  the  field  horsetail  and  the  wood 
horsetail  that  the  beginner  might  fancy  it  a  hybrid 
between  them,  but  students  of  the  equisetums  do  not  hold 
this  view.  The  three  forms  of  fronds,  however,  are  of 
interest  in  showing  in  a  single  species  the  relationship 
between  fertile  and  sterile  shoots. 

The  Wood  HorsetaiL 

In  his  book,  *'The  Fern  Garden,"  Shirley  Hibbard 
characterizes  the  wood  horsetail  {Equisetmn  silvatiaun) 
as  **  the  most  elegant  of  all  the  plants  upon  the  face  of 
the  earth."  This  may  seem  like  extravagant  praise  to 
those  who  have  never  chanced  upon  its  graceful  green 
spires  reared  in  the  shadows  of  some  moist  woodland  ; 
but  to  those  who  have,  it  will  probably  seem  not  much 
overdrawn.  If  not  ready  to  admit  its  claim  to  be  the 
most  elegant  of  plants,  they  will  scarcely  deny  that  it  is 
the  handsomest  of  the  equisetums  and  fully  the  equal 
of  any  other  plant  whose  beauty  depends  entirely  upon 
the  outline  and  cutting  of  leaf  and  stem. 


56  THE  HORSETAILS. 

As  ill  all  species  of  liquisctuin  in  which  tlierc  is  a 
marked  difference  between  fertile  and  sterile  fronds,  the 
fertile  are  first  to  push  up,  appearing  shortly  after  those 
of  the  field  horsetail  and  in  their  early  stages  scarcely  to 
be  distinguished  from  them.  There  is,  however,  from 
the  beginning,  a  greenish  tinge  to  the  stems,  presaging 
their  subsequent  vegetative  functions,  while  the  sheaths, 
rather  longer  for  their  width  than  in  Eqiiisettini  arvcnse, 
are  tipped  with  long  teeth  of  bright  reddish  brown.  At 
first  the  sheaths  are  dilated  upward,  but  they  soon 
change  to  urn-shape  on  account  of  the  swelling  buds 
within.  The  fruiting  cone  is  about  an  inch  long  and 
one  third  as  wide.  It  is  of  the  same  general  colour  as 
the  stem,  and  consists  of  the  usual  number  of  sporophylls 
borne  above  the  topmost  sheath  on  a  pedicel  two  or 
three  inches  long. 

Before  the  spores  are  ripe,  whorls  of  branches  have 
begun  to  develop  from  the  upper  joints.  Sometimes 
even  the  lowest  whorl  of  sporophylls  push  out  a  few 
short  branches.  The  fruiting  parts  usually  wither  as 
soon  as  the  spores  are  shed,. while  the  rest  of  the  stem 
continues  to  develop  branches  and  soon  is  hard  to  dis. 
tinguish  from  the  wholly  sterile  fronds,  except  that  the 
sheaths  are  somewhat  larger  and  the  apex  of  the  stem 
not  so  slender  and  tapering. 

The  sterile  fronds  closely  follow  the  fertile,  and  when 
fully  developed  may  reach  a  height  of  three  feet.  The 
stem  is  slender  and  has  twelve  to  eighteen  grooves,  the 
ridges  between  being  rough  with  small  particles  of  silex^ 
but  never  rough  enough  to  be  noticeable.  The  lower 
nodes  do  not  produce  branches,  but  above  there  is  a  whorl 
of  branches  at  each  node,  the  lowermost  reaching  a  length 
of  three  to  six  inches,  and  the  others  gradually  decreas- 


WOOD  HORSETAIL.     Eqmsettwi  stlvatkinn. 
Sterile  frond. 


r^ 


Ip-V-i 


WOOD  HORSETAIL.    Equiscium  silvaticum. 
Fertile  fronds. 


THE  HORSETAILS. 


57 


ing  in  length  to  the  apex  of  the  frond.  Occasionally, 
however,  the  branches  at  the  apex  are  nearly  as  long 
as  those  below.  The  branches  of  each  whorl  spread 
out  nearly  horizontally,  and  each  is  again  branched, 
the  longest  branchlets  being  nearest  the  stem.  The 
effect  produced  is  that  of  a  series  of  circular  green  plat- 
forms diminishing  in  size  upward,  with  the  main  stem 
as  a  central  column.  The  fine  and  slender  branchlets 
with  drooping  tips  make  the  whole  frond  exceedingly 
delicate  and  graceful.  This  is  the  only  species  in  the 
world  in  which  the  branches  are  again  regularly 
branched.  In  some  cases  the  secondary  branches  are 
also  branched. 

The  rootstock  of  the  wood  horsetail  is  slenderer  than 
that  of  Equisetum  arvense;  otherwise  it  much  resembles 
it.  The  sheaths  of  the  secondary  rootstocks,  however, 
are  better  developed,  though  the  buds  from  which  the 
fertile  spikes  are  produced  are  smaller.  The  secondary 
rootstocks  also  bear  tubers,  though  not  so  abundantly 
as  does  Eqiiisetimi  arvense  or  Eqiiisetiivi  tebnateia. 
These  tubers  are  usually  much  larger  than  those  of 
Equisettiin  arvense  and  are  ovate  instead  of  spherical. 

The  wood  horsetail  is  found  in  America  from 
Virginia,    Michigan,   Iowa,  and   Nebraska  to   the  Arctic 


WOOD  HORSETAIL  BUDS  AND  TUBERS. 


58  THE  HORSETAILS. 

Circle,  but  apparently  does  not  occur  in  the  United 
States  west  of  the  Rocky  Mountains.  It  is  also  found 
in  the  northern  parts  of  both  Europe  and  Asia.  It 
delights  in  rich  moist  soil,  its  favourite  haunts  being 
deep  woodlands  and  the  banks  of  shaded  streams.  It 
is  rarely  if  ever  found  in  fields,  though  it  may  persist  in 
pastures  and  swamps  for  some  time  after  the  sheltering 
'trees  have  been  removed.  Like  the  field  horsetail,  it  is 
sometimes  called  "  bottle-brush  "  in  allusion  to  its  fronds. 
It  has  the  reputation  of  fruiting  sparingly,  and  the  fruit- 
ing-spikes  are  certainly  not  so  abundant  as  those  of 
other  species  when  the  plant  grows  in  deep  shade, 
though  in  exposed  positions  they  may  always  be  found 
in  season.  Plants  that  extend  their  bounds  by  root- 
stocks  or  bulbs  usually  produce  few  seeds  or  spores,  and 
our  plant  seems  to  be  no  exception  to  the  rule.  Accord- 
ing to  Withering,  horses  are  fond  of  this  species,  and  in 
the  north  of  Europe  it  is  said  to  be  sometimes  pre- 
served for  winter  fodder. 

The  wood  horsetail  readily  adapts  itself  to  a  life  in 
the  fern  garden  if  given  a  fat  soil  and  plenty  of  shade 
and  moisture.  It  spreads  nearly  as  rapidly  as  the  field 
horsetail  and  presents  a  far  more  attractive  appearance. 
It  may  also  be  grown  in  the  greenhouse.  In  such  situ- 
ations the  rootstocks,  being  prevented  from  following 
their  inclination  to  spread  about,  send  up  great  num- 
bers of  the  graceful,  emerald-green  fronds  that  are  the 
delight  of  all  v/ho  see  them. 

The   Water  Horsetail. 

Of  all  our  American  equisetums  the  water  horsetail 
(Eqiiisetum  fluviatilc)  is  undoubtedly  first  to  start  into 
growth  each  spring,  but,  owing  to  the   length   of  stem  it 


WATE  R  H  0 RSETA I L .     Eqiiisetum  fluviatile. 


THE  HORSETAILS.  59 

produces  before  fruiting,  it  does  not  put  forth  its 
catkins  until  several  other  species  have  shed  their 
spores.  As  its  name  implies,  this  species  is  usually 
found  in  several  inches  of  water,  and  the  rootstock, 
lying  in  the  unfrozen  mud,  early  feels  the  vernal  impulse 
and  starts  the  young  stems  upward  soon  after  the  ice 
has  disappeared  and  while  yet  the  meadow  grasses  are 
brown  and  sere.  These  developing  stems  are  most 
striking  objects,  being  ringed  at  close  intervals  with 
many  circles  of  the  black  saw-like  teeth  of  the  sheaths. 
Sometimes  as  many  as  thirty  circles  of  teeth  may  be 
found  on  the  stem  before  it  has  pushed  above  the  sur- 
face of  the  water.  Growth,  as  in  the  other  species,  is 
principally  a  matter  of  lengthening  internodes. 

About  the  last  week  in  May,  in  the  southern  part  of 
its  range,  the  stems  that  are  to  produce  the  spores 
develop  a  fruiting-catkin  an  inch  or  more  in  length  and  a 
third  as  thick.  Fertile  fronds  are  ordinarily  not  abun- 
dant, but'  it  is  said  that  a  period  of  drouth  will  greatly 
increase  their  numbers.  As  soon  as  the  spores  are  shed, 
this  catkin  withers,  but  from  the  sheaths  of  the  stem 
that  bears  it  slender  branches  have  been  developing,  and 
these,  lasting  through  the  season,  make  the  stems  look 
so  much  like  the  regularly  sterile  ones  that  they  cannot 
be  distinguished  from  them  at  first  glance.  Since  the 
production  of  spores  is  a  heavy  draft  upon  the  vigour  of 
the  stem,  the  fertile  fronds  are  usually  overtopped  by 
the  others,  which  often  reach  a  height  of  five  feet  or 
more. 

There  is  no  uniformity  in  the  manner  of  branching,  as 
in  most  other  species,  but  each  stem  is  likely  to  vary  the 
pattern  somewhat.  In  general,  however,  the  lowest  ten 
or   twelve   joints   are    unbranched,    then    come    several 


6o  THE  HORSETAILS. 

whorls  of  simple  branches  which  grow  successively  shorter 
upward,  ceasing  entirely  six  inches  or  a  foot  below  the 
apex,  which  thus  extends  above  the  bushy  portion  as  a 
slender  whip-like  prolongation.  The  lowest  branches 
are  often  a  foot  or  more  in  length  and  seem  more  in  the 
nature  of  secondary  stems.  Usually  the  branches  are 
much  shorter  and  are  disposed  in  regular  horizontal 
whorls,  though  often,  especially  toward  the  apex  of  the 
stem,  the  symmetry  of  the  whorls  is  destroyed  by  the 
failure  of  certain  branches  to  develop.  It  is  not  uncom- 
mon, also,  for  both  fertile  and  sterile  stems  to  be  entirely 
without  branches,  in  which  event  they  might  be  mis- 
taken for  forms  of  the  common  scouring-rush.  In 
branched  forms  the  lowest  branches  may  occasionally 
put  forth  a  few  branchlets,  but  usually  the  branches  are 
simple. 

The  stems  of  this  species  are  smooth  and  contain  from 
ten  to  thirty  shallow  grooves  which  are  not  very  promi- 
nent in  the  living  plant,  but  become  more  marked  in  the 
dried  specimens.  The  sheaths  are  like  the  stem  in 
colour,  about  as  broad  as  long,  and  closely  appressed  to 
it.  The  teeth,  separated  from  one  another  by  rounded 
sinuses,  are  short,  sharp,  and  nearly  black  in  colour. 
According  to  A.  A.  Eaton,  the  number  of  grooves  in  the 
stem  and  the  number  of  leaves  in  the  sheath  increase 
upward,  so  that  the  upper  joints  often  contain  a  third 
more  than  those  below.  The  stem  is  hollow  for  about 
four  fifths  of  its  diameter,  none  of  our  other  species 
equalling  it  in  this  respect.  The  carinal  canals  are 
apparently  always  present,  but  the  vallecular  are  often 
wanting  in  growing  stems,  though  very  prominent  in 
older  ones.  The  rootstock,  which  is  about  as  thick  as 
the  stem,  is  also  hollow.     It  is  usually  not  very  deep  in 


PLATE  III.    WATER    HORSETAIL.     Eqinsetum  fluviatile. 

CCPYRIOHT,    1905,    BY    FREDERICK    A.    STOKES  COMPANY 


THE  HORSETAILS. 


6i 


SECTION  OF  STEM. 


the  soil,  perhaps  because  the  overlying  water  makes  it 
unnecessary  by  keeping  out  the  frost.  As  the  aerial 
stems  rise   through   the  mud,  they  send  out  roots  from 

the  basal  joints,  and  it  is  pro- 
bable that  if  the  entire  stem 
was  buried  in  the  mud  it 
would  promptly  take  up  the 
offices  of  a  rootstock.  Branches 
of  the  rootstock  sometimes 
produce  tubers  which  are  de- 
scribed as  ''  about  the  size  of  a 
nutmeg,  but  shaped  like  a  fig." 
Half  a  dozen  have  been  found 
on  a  single  branch. 
This  species  has  very  little  silica  in  its  outer  coat  and 
is  one  of  the  smoothest  of  the  equisetums.  It  is  readily 
eaten  by  cattle,  and  is  said  to  be  fed  to  cows  in  Sweden 
to  increase  the  flow  of  milk.  In  Lapland,  reindeer  eat  it 
even  when  dried,  though  they  will  not  touch  hay,  and 
Linnaeus  recommended  that  it  be  gathered  and  preserved 
with  reindeer-moss  for  winter  use.  When  abundant  it 
is  occasionally  cut  for  hay  in  America.  According  to 
Haller,  the  Romans  were  accustomed  to  eat  it.  Musk- 
rats  are  very  fond  of  the  young  stems  and  often  work 
much  havoc  among  them  just  as  they  are  pushing  up  to 
the  surface  of  the  water. 

The  water  horsetail  extends  from  Virginia,  Kansas, 
and  Washington  to  the  far  North,  being  not  uncommon 
in  the  northern  United  States,  though  not  always  present 
in  what  appear  to  be  favourable  locations  for  it.  While 
it  prefers  to  grow  in  several  inches  of  water  and  is  com- 
monly found  in  the  quiet  reaches  of  shallow,  slow- 
moving  streams  or  on  the  margins  of  lakes  and  ponds,  it 


62  THE  HORSETAILS. 

is  often  found  in  mud  or  moist  sand  and  gravel  at  mid- 
summer, owing  to  the  lessening  of  the  water  by  drouth. 
Along  certain  rivers  it  forms  a  continuous  border  for 
miles,  almost  to  the  complete  exclusion  of  other  plants. 
It  occurs  also  in  northern  Europe  and  Asia,  belting  the 
earth  in  a  zone  nearly  a  thousand  miles  wide.  It  is  a 
polymorphic  species  and  in  some  of  its  disguises  is  hard 
to  identify.  Its  irregular  branching  and  appressed 
sheaths  are  most  characteristic  features.  It  is  so  much 
like  the  marsh  horsetail  and  the  shore  horsetail  in 
appearance  that  the  novice  may  have  trouble  in  dis- 
tinguishing between  them,  but  since  this  is  the  only  one 
of  the  trio  that  is  abundant  it  is  safe  to  give  it  the 
benefit  of  any  doubt  that  may  arise. 

In  many  books  the  species  is  called  Equisctiun  liniosuiii, 
hw\.  fluviatile  is  the  older  name.  This  difference  in  age, 
however,  well  illustrates  the  small  differences  that  govern 
the  work  of  botanists.  The  name  fluviatile  stands  just 
before  liuiosnui  in  **  Species  Plantarum  "  and  is,  therefore, 
older  by  the  mere  length  of  time  it  takes  for  the  printer 
to  set  a  line  of  type  ;  and  yet  this  is  held  sufficient  to 
make  the  one  for  ever  right  and  the  other  for  ever  wrong. 
Limostun  is  now  used  to  characterize  the  nearly  un- 
branched  form.  Among  its  common  names  are  **  mud 
horsetail,"  "  joint-grass,"  and  "  paddock-pipes."  The 
last  name  is  also  given  to  Eqtiisettun  arvcnse,  but  is  more 
appropriately  applied  to  this  species,  since  it  is  found 
in  the  places  beloved  of  '*  paddocks,"  as  frogs  were 
commonly  called. 

The  Marsh  Horsetail. 

At  first  glance  it  is  possible  to  mistake  the  marsh 
horsetail  [Eqiiisctuin  palnstrc)  for   the    water  horsetail, 


MARSH   HORSETAIL.     Equisetum  pahcsire. 


THE  HORSETAILS.  63 

but  the  fact  that  Equisctuui palustre  is  rare  in  the  settled 
parts  of  America  will  save  the  collector  from  making 
many  mistakes  of  this  kind.  Should  he  by  chance 
collect  the  rarer  species,  he  will  discover,  by  comparing 
it  with  the  other,  that  there  are  many  small  though 
important  points  of  difference.  Although  the  two  are 
so  much  alike  in  habitat  and  structure,  the  stems  of 
Equisetiim palustre  are  more  deeply  grooved  and  have 
a  smaller  central  hollow,  the  sheaths  are  dilated  upward, 
and  the  rootstock  is  solid,  all  of  which  are  the  exact 
opposites  of  the  conditions  that  prevail  in  the  water 
horsetail. 

The  marsh  horsetail  is  a  smaller  species  than  Equisetiim 
fluviatile,  seldom  reaching  a  height  of  two  feet,  and, 
though  delighting  in  rich  moist  soil,  is  not  so  frequently 
found  growing  in  the  water.  The  stem  is  slender  and 
often  branched  from  the  very  base,  producing  regular 
whorls  of  short  branches.  Occasionally  the  basal 
branches  may  be  much  longer — perhaps  two  thirds  the 
length  of  the  main  stem  —  and  may  be  borne  half  erect 
like  secondary  stems.  Fertile  and  sterile  stems  are 
much  alike,  except  that  in  the  one  the  main  stem  is 
terminated  by  a  catkin,  and  in  the  other  the  apex  ends 
in  a  slender  unbranched  tip. 

The  catkins  are  unusually  large  for  the  size  of  the 
plant,  being  an  inch  or  more  long  and  about  a  third  as 
wide.  They  are  borne  above  the  last  whorl  of  branches 
on  slender  pedicels  an  inch  or  more  long,  and,  as  is  the  rule 
among  horsetails,  perish  as  soon  as  the  spores  have  been 
dispersed.  The  species  begins  to  fruit  early  in  summer, 
and  a  succession  of  new  stems  may  often  prolong  the 
season  into  autumn,  though  the  greatest  number  of 
catkins  will    be    found    early    in    the   year.     Sometimes 


64  THE  HORSETAILS. 

the  long  basal  branches,  or  a  few  of  those  near  the  tip, 
may  bear  small  cones  of  fruit  also. 

The  sheaths  in  both  fertile  and  sterile  fronds  are 
longer  than  broad,  greenish  in  colour,  with  rather  loose 
black  teeth  bordered  with  white  margins.  They  invest 
the  stem  quite  loosely,  being  dilated  upward.  The 
leaves  are  convex,  grooved  in  the  middle  at  the  apex, 
and  strongly  keeled  below. 

The  stems  have  from  five  to  twelve  broad,  deep 
grooves,  the  ridges  separating  them  being  narrower, 
sharply  elevated,  and  rounded  on  the  back.  These 
grooves  are  fewer  in  number  than  in  Equisetiim  fltiviatile 
and  in  fresh  specimens  are  much  more  prominent. 
When  dried  for  the  herbarium  the  difference  is  not  so 
marked.  The  branches  usually  contain  fewer  angles 
than  the  stem,  and  their  sheaths  are  also  green  and 
dilated.  The  central  cavity  of  the  stem  occupies  about 
one  sixth  of  the  diameter,  a  character  which  alone  is 
sufficient  to  distinguish  it  from  Eqitisetiivi  fijiviatile. 
Carinal  and  vallecular  canals  are  also  present.  Although 
so  much  like  the  water  horsetail,  it  occasionally  pro- 
duces forms  that  are  very  much  like  varieties  of 
Equisefmn  arvensc,  and  the  likeness  is  heightened  by 
the  similarity  of  the  internal  structure  of  the  stem. 

The  marsh  horsetail  has  been  reported  from  all  the 
New  England  States  except  Rhode  Island,  and  from 
Illinois  and  Washington.  In  none  of  these  States  is 
it  abundant  or  extensively  distributed,  and  in  many 
the  record  rests  upon  a  single  locality.  It  is  more 
plentiful  in  British  America,  extending  to  Alaska  and 
Hudson  Bay.  It  grows  among  grasses  in  damp  mead, 
ows,  in  moist  woodlands,  and  in  open  swamps.  Dr.  C. 
B.  Graves  has  found  it  in  Connecticut  in  meadows  sub- 


A  Form  of  Equisetum  Wtorale, 


THE  HORSETAILS.  65 

ject  to  frequent  overflow.  It  occasionally  forms  thick- 
ets, as  the  other  species  do,  but  appears  not  to  be  as 
gregarious  as  some.  In  the  colder  parts  of  the  Old 
World  the  plant  is  more  plentiful,  but  becomes  rare  in 
southern  Europe.  Mr.  A.  A.  Eaton  notes  in  the  Fern 
Bulletin  that  the  Indians  of  Alaska  make  baskets  of  the 
rootstocks  of  some  species  of  Equisetiim  and  concludes 
that  this  is  the  one  used. 

"The   Shore  Horsetail. 

Many  botanists  are  inclined  to  question  the  right  of 
the  shore  horsetail  (Equisetum  littorale)  to  be  called  a 
distinct  species.  It  presents  a  most  perplexing  series  of 
forms  and  appears  never  to  be  twice  alike.  Now  it  is 
tall  and  abundantly  branched,  like  Equisetum  fluviatile ; 
again  it  may  be  prostrate  or  decumbent,  like  forms  of 
Eqttisettnn  arvense;  and  at  other  times  may  simulate 
Equisetum  silvaticum  or  Equisetum palustre.  The  sheaths 
may  be  appressed  or  dilated,  the  central  cavity  may 
occupy  one-half  or  two-thirds  the  diameter  of  the  stem, 
and  the  stem  itself  may  be  either  branched  or  simple. 
Still  more  remarkable,  the  spores  are  abortive  and  have 
no  elaters,  this  being  the  only  form  of  Equisetum  having 
this  latter  characteristic.  All  these  differences  seem 
best  explained  by  the  theory  that  the  forms  given  the 
name  of  Equisetum  littorale  are  really  hybrids  between 
some  other  species,  and  while  the  author  accepts  this 
theory  the  form  is  here  treated  as  a  species  in  order  not 
to  confuse  the  novice,  who  will  find  it  listed  as  a  species 
in  all  other  American  works. 

Since  the  varieties  of  the  shore  horsetail  most  often 
resemble  specimens   of  Equisetum  fluviatile  and  Equise- 


66  THE  HORSETAILS. 

tnm  arvense,  it  has  been  conjectured  that  these  species 
are  its  parents.  In  both  structure  and  habit  it  is  about 
halfway  between  the  two,  and  in  some  localities  a  series 
of  intergrading  forms  could  be  selected,  leading  almost 
imperceptibly  from  one  to  the  other.  The  strongest 
point  made  against  the  theory  of  the  hybridizing  of 
these  two  species  is  the  fact  that  they  do  not  fruit  at 
the  same  time,  but  in  reality  this  may  be  indirect  evi- 
dence in  its  favour.  Equisetum  prothallia  may  live  for 
some  months  if  unfertilized,  giving  ample  opportunity 
for  crossing  between  species  that  do  not  fruit  at  the 
same  time,  while  the  infrequency  of  such  an  occurence 
would  account  for  the  rarity  of  the  hybrid  form.  Since 
in  all  the  Equiseta  the  sexes  are  on  separate  prothalli, 
it  would  be  a  much  easier  matter  to  prove  or  disprove 
this  theory  than  it  would  be  in  the  case  of  ferns  where 
both  sexes  are  on  the  same  prothallium. 

As  commonly  described,  Equisctwn  littorale  is  three 
feet  or  less  in  height,  usually  erect,  with  slender  stems 
containing  from  six  to  twenty  grooves.  In  some  speci- 
mens the  stems  are  unbranched,  in  others  branched  only 
in  the  lower  part,  and  in  still  others  branches  occur  nearly 
to  the  top.  In  all,  the  upper  nodes  are  prolonged  into  a 
whip-like  tip  which  in  fruiting  specimens  bears  a  small 
fruit-cone.  Usually  the  stems  with  cones  are  not 
branched  as  much  as  the  others.  At  the  base  of  the 
stem  the  sheaths  are  dark  in  colour;  above,  they  are 
green  with  short,  narrow,  dark-coloured  teeth  bordered 
with  white.  The  sheaths  may  be  appressed  near  the 
base  of  the  stem,  but  beyond  they  usually  widen  out 
The  catkins  are  borne  on  very  slender  pedicels  and  often 
do  not  become  much  larger  than  pepper-corns,  though 
occasionally  they   may  attain  a  length   of  half  an  inch. 


I    \ 


/^ 


FORMS  OF  SHORE   HORSETAIL.     Kqiiisehim  littorale. 


THE  HORSETAILS.  67 

The  sporophylls  do  not  draw  apart  at  maturity,  as  in 
other  species  ;  but  this  is  of  no  consequence,  since  the 
spores  will  not  germinate. 

The  range  of  Equisetiun  littorale  is  given  as  from  New 
Jersey  and  Pennsylvania  to  Minnesota  and  northward. 
It  is  only  occasionally  found,  but,  where  present  at  all, 
often  occurs  in  great  abundance  notwithstanding  the 
abortive  spores,  since  it  spreads  rapidly  by  means  of  its 
rootstocks.  Mr.  Eaton  notes  that  along  the  lower  Mer- 
rimac  River  the  plant  is  so  abundant  as  to  be  cut  for  hay 
under  the  name  of  *'  joint-grass."  It  prefers  a  drier  location 
than  does  Equisetum  fliwiatile,  but  both  may  be  found 
together.  According  to  Mr.  Eaton  the  two  species  may 
readily  be  distinguished  in  the  field  by  a  section  of  the 
stem  just  below  the  joints.  In  stems  of  Equisetum  litto- 
rale the  cross-section  presents  a  star-like  opening,  while 
that  of  Equisetum  fluviatile  is  larger  and  circular.  In 
Equisetum  littorale  the  vallecular  canals  are  always  pres- 
ent, but  they  are  absent  in  Equisetum  fluviatile  except  in 
large  or  old  stems.  It  is  easily  distinguished  from  Equi- 
setum fluviatile,  however,  by  the  fact  that  the  sheaths 
are  never  so  closely  appressed  to  the  stem,  the  grooves 
of  the  stem  are  fewer  and  deeper,  and  the  central  hollow 
is  not  so  large.  The  shore  horsetail  is  also  found  in  the 
Old  World,  extending  from  England  to  France,  Austria, 
Russia,  and  Scandinavia. 


THE  LYCOPODIACE/E,  OR  CLUB- 
MOSSES. 


A  moss  Capsule 


THE  LYCOPODIACE^. 

N  the  early  days  of  plant  study,  long 
before  the  art  of  simpling  had  crys- 
tallized into  the  science  of  botany, 
people  had  very  hazy  ideas  regarding 
the  afifinities  of  plants,  and  the  most 
diverse  were  often  placed  in  the  same 
group.  The  Lycopodiaceae  were  then 
thought  to  be  mosses,  but  the  fact  that 
they  bear  their  spores  in  club-shaped 
spikes  did  not  escape  notice,  and  they 
were  accordingly  called  club-mosses  to 
distinguish  them  from  the  true  mosses, 
which  bear  their  spores  in  capsules. 
Although  everyone  nowadays  knows 
that  the  club-mosses  are  not  very 
closely  related  to  the  mosses,  the  name 
is  so  convenient  and  descriptive  that  it 
is  likely  always  to  be  used  in  speaking 
of  them. 

In  appearance  the  club-mosses 
are  as  different  from  thescouring- 
rushes  as  one  could  well  imagine. 
The  most  noticeable  character- 
istics of  the  scouring-rushes  are 
the  great  development  of  stem 
and  the  small  functionless  leaves, 
while  the  club-mosses  are  remark- 


72  THE  LYCOPODIACE>e. 

able  for  their  leaves,  which,  though  small,  are  so  numer- 
ous as  often  to  make.it  easier  to  infer  the  presence  of  a 
stem  than  actually  to  see  it. 

In  our  species  of  Lycopodium  there  is  nothing  that  can 
be  called  a  rootstock,  unless  we  are  inclined  to  call  the 
main  axis  a  combination  of  rootstock  and  stem.  In  some 
species  this  axis  is  above  ground  and  covered  on  all  sides 
with  the  leaves  ;  in  others  it  is  beneath  the  surface  or 
buried  in  the  debris  that  covers  the  forest  floor ;  and  in 
still  others  it  creeps  upon  the  surface  of  the  earth  with 
roots  on  the  under  surface  and  leaves  on  the  upper.  In 
all,  it  may  send  out  roots  whenever  it  comes  in  contact 
with  the  earth.  It  is  noticeable,  however,  that  there  is 
only  one  growing  end  to  this  axis,  and  that  the  other  is 
more  rootlike  in  appearance.  As  the  stem  continues  to 
add  to  its  length  at  the  growing  end,  it  as  slowly  dies  at 
the  other,  and  thus  the  plants  year  by  year  move  slowly 
forward,  and,  though  rooted  in  the  soil,  no  individual 
plant  occupies  quite  the  same  position  for  two  successive 
seasons.  Indeed,  although  the  life  of  the  plant  has 
continued  uninterruptedly,  it  may  be  fairly  questioned 
whether  after  some  years  it  is  the  same  individual.  The 
leaves  are  not  the  same,  the  roots  and  stem  are  not  the 
same,  and  it  does  not  occupy  the  same  place  in  the 
woodland. 

In  some  species  the  main  axis  reaches  a  length  of  ten 
or  fifteen  feet ;  in  others,  less  than  half  as  many  inches. 
It  usually  takes  a  course  parallel  to  the  surface  of  the 
earth  and  occasionally  sends  out  secondary  stems  that 
are  exactly  like  it  in  growth  and  function.  From  all 
these  stems  spring  the  short  upright  branches  that  form 
the  noticeable  part  of  the  plant.  The  leaves  are  small 
and  pointed,  with  a  distinct  midrib,  which,  however,  does 


THE  LYCOPODIACE/E. 


72, 


not  extend  to  the  apex.  They  are  arranged  on  the  stem 
and  branches  in  from  four  to  sixteen  rows,  the  number 
depending  upon  the  species.  These  numerous  short 
leaves,  mostly  standing  out  from  the.  stem,  make  many 
species  look  exceedingly  like  mosses,  especially  when 
not  m  fruit ;  but  even  then  they  may  be  distinguished 
from  mosses  by  the  fact  that  their  stems  contain  pro- 
nounced fibro-vascular  bundles,  while  those 
of  the  mosses  do  not. 

The  lycopodiums  are  among  the  latest  of 
the  fern  allies  to  fruit.  Some  in  the  northern 
States  do  not  shed  their  spores 
until  late  in  October.  The  spore- 
cases  are  always  borne  at  or  near 
the  tips  of  the  branches.  In  one 
type  they  are  in  the  axils  of 
unchanged  leaves ;  in  another  the 
leaves  are  more  or  less  reduced 
and  yellow  in  colour,  forming 
cone-like  spikes  which  in  some 
species  are  borne  above  the 
foliage  leaves  on  slender  stems.  The  sporangia  or  spore- 
cases,  one  in  the  axil  of  each  leaf,  are  one-celled  kidney- 
shaped  structures  with  thin  tough  walls.  The  spores  are 
very  abundant,  and  bright  yellow  in  colour.  Undevel- 
oped spore-cases  are  often  found  above  and  below  the 
zone  of  fruitful  sporangia. 

The  prothallium  of  Lycopodium  is  still  imperfectly 
known.  In  the  species  in  which  it  has  been  studied  it 
usually  consists  of  a  cylindrical  mass  of  pale  cells  either 
wholly  or  partly  underground  and  bearing  both  male  and 
female  elements.  These  pale  prothallia,  lacking  the 
green  colouring-matter  of  ordinary  plants,  cannot  secure 


Sporophyll  and 
Spore-case, 


A  Fruiting- 
spike. 


74 


THE  LYCOPODIACE^. 


their  food  as  other  plants  do,  and  so  have  set  up  a  part- 
nership with  a  fungus  which  is  always  present  and  aids 
in  the  work.  The  prothallia  of  certain  exotic  species  liv- 
ing on  trees  are  slender,  much-branched  structures  and 
are  saprophytic,  that  is,  they  live,  like  the  mushrooms, 

upon  the  decayed' 
vegetable  matter  in 
their  vicinity.  Be- 
cause of  this  asso- 
ciated fungus  it  is  a 
difficult  matter  t  o 
grow  the  prothallia 
of  the  Lycopodiacese, 
and  that  of  many 
species  has  never 
been  seen.  Further 
observations  of  these 
structures  are  very 
much  to  be  desired„ 
It  is  suggested  that 
the  prothallia  might 
be  raised  by  infest- 
ing them  with  spores 
of  the  fungus.  This 
might  possibly  be 
done  by  watering  the 
spores  with  water  in 
which  the  roots  of  the 
lycopodiums  have 
been  soaking.  This  theory  is  being  put  to  a  practical 
test,  but  the  experiments  have  not  progressed  far  enough 
to  have  the  results  included  here. 

In  all  flowering  plants,  and  in    nearly  all  others,  the 


SPOROPHYLLS  OF  LYCOPODIUM. 
I.  L.  complanatum.  2.  L.  alpinum.  3.  L.  sabinse 
folium,  4.  L.  clavatum.  5.  L.  Sitchense.  6.  L 
cernuum.  7.  L.  annotinum.  8.  L.  Carolinianum, 
9.  L.  inundatum.  10.  L.  obscurum,  11.  L.  alopec 
uroides. 


THE  LYCOPODIACE/E.  75 

roots,  penetratip.g  the  earth,  give  off  rootlets  here  and 
there  as  conditions  require  ;  but  in  the  Lycopodiums  the 
roots  branch  dichotomously,  dividing  into  two  equal 
branches  which  may  again  divide  in  the  same  way.  The 
roots  do  not  seem  to  have  any  special  point  on  the  stem 
from  which  to  grow,  but  develop  on  any  part  that 
touches  the  soil. 

There  are  about  a  hundred  species  of  Lycopodiiim 
known  at  present.  The  majority  are  found  in  the 
warmer  regions  of  the  world,  where  they  often  grow  on 
the  branches  of  trees^  many  feet  from  the  ground. 
Other  species  clamber  over  the  vegetation  like  the  climb- 
ing ferns.  Our  species  are  all  low  and  inconspicuous 
plants,  keeping  close  to  the  earth  on  moors  or  in  swamps, 
woodlands,  and  thickets.  Some  are  very  hardy,  electing 
to  grow  in  barren  rocky  wastes  on  the  very  edge  of  the 
world,  as  it  were.  They  are  often  found  in  the  greatest 
abundance  on  rough  mountain-tops  or  bordering  the 
roadsides  in  elevated  districts.  Some  extend  northward 
to  the  Arctic  Circle  and  beyond.  All  our  species  are 
perennial,  and  not  only  are  the  leaves  of  most  of  them 
evergreen,  but  many  appear  to  last  for  several  years. 

The  lycopodiums  of  the  present  are  mere  rem- 
nants of  the  race.  During  the  Coal  Period  they  were 
most  luxuriant,  and  the  various  forms  attained  the 
height  of  trees.  Of  these  the  lepidodendrons  and  sigil- 
larias  are  well  known,  while  the  roots  of  other  species 
were  once  erroneously  referred  to  a  genus  called  Stig- 
maria.  The  spore-cases  of  some  of  these  old  lycopo- 
diums have  been  so  carefully  preserved  by  nature  that 
their  structure  may  still  be  discerned.  It  is  a  curious 
fact  that  the  ancient  species  were  heterosporous,  with 
two  kinds  of  spores  like  Isoeies  and  Selaginclia,  while 
living  lycopodiums  have  spores  all  alike. 


76  THE   LYCOPODIACE^. 

The  club-mosses  are  probably  the  best  known  of  the 
fern  allies.  During  the  winter  holidays,  great  quanti- 
ties of  certain  species  are  used  in  festoons,  wreaths,  and 
other  decorations.  The  steadily  increasing  demand  for 
such  greenery  is  pushing  several  of  the  more  decorative 
species  to  the  verge  of  extinction,  since  they  reproduce 
very  slowly.  The  spores  of  some  species  form  an  import- 
ant article  of  commerce,  and,  under  the  name  of  lyco- 
podium  powder,  may  be  found  in  any  drug  store.  They 
contain  more  than  half  their  bulk  in  oil,  and,  if  sprinkled 
in  the  flame  of  a  candle,  may  be  seen  to  ignite  with  a 
flash.  They  have  been  extensively  used  in  fireworks 
under  the  names  of  vegetable  brimstone  and  vegetable 
sulphur.  If  sprinkled  thickly  over  the  surface  of  a  glass 
of  water,  one  may  plunge  his  finger  to  the  bottom  with- 
out its  being  wetted.  Their  chief  value  to  the  druggist 
is  for  dusting  pill-boxes,  to  keep  the  pills  from  sticking 
together.  Various  species  of  Lycopodium  have  been 
used  in  dyeing,  and  some  are  emetic,  but  their  medicinal 
effects  are  too  violent  to  entitle  them  to  a  place  among 
drugs  of  the  present.  Most  species  are  also  more  or 
less  astringent. 

The  word  Lycopodium  comes  from  two  Latin  words 
meaning  "wolf"  and  *' foot,"  but  the  reason  for  its 
application  to  these  plants  is  not  apparent  unless  it  is  in 
allusion  to  the  habit  they  have  of  growing  in  wild  and 
inhospitable  regions  where  only  the  foot  of  the  wolf  is 
likely  to  tread. 


Key  To  The  Lycopodiums. 

I.  —  Sporangia  in  the  axils  of  ordinary  leaves 

Leaves  flat.     Lowland  species .     .  L.  hccididiim 

Leaves  curved  upward.     Mountain  species    L.  sclago 
n.  —  Sporangia  in  cone-like  spikes 

Sterile  stems  prostrate  ;  fertile,  erect,  unbranched 

Prostrate  stems  usually  branched  Z.  alopecuroides 
Prostrate  stems  short,  seldom  branched 

Rooting  throughout  .     L.  Caroliniajiuin 

Rooting  at  base  and  tip  only  .     Z.  imindatum 
Fertile  and  sterile  stems  erect;  rootstock  creeping 
Cones  closely  sessile 

Averaging  an  inch  or  more  long     Z.  obsctirmn 
Averaging  less  than  an  inch  long 

Z.  ajinolimnn 
Averaging  less  than  half  an  inch  long 

Z,  ceniiciini 
Cones  apparently  stalked 

Branches  about  four-sided    .  Z.  alpinmn 

Branches  round 

Leaves  bristle-tipped,  \  inch  long 

Z.  davatiwi 
Leaves  not  bristle-tipped,  shorter 

Z.  Sitche7tse 
Branches  flattened 

Cones  two  to  four,  peduncle  long,  stout 

Z.  co7nplanatiini 
Cones  one  to  three,  peduncle  short,  slender 
Z.  sabmccfolium 


THE  TRAILING  LYCOPODIUMS. 


THE  TRAILING  LYCOPODIUMS. 

IKENESSES  among  the  club-mosses  are  so 
noticeable  that  any  member  of  the  group  is 
easily  recognized.  Certain  differences  in  the 
manner  of  growth,  however,  make  them 
separable  into  two  groups,  in  one  of  which 
the  species  are  small  and  the  plant  body 
mostly  erect  or  decumbent,  while  in  the 
other  the  plants  are  larger  and 
the  principal  stems  long  and 
trailing.  These  latter  are  the 
species  that  figure  in  our  holiday 
decorations,  and  as  most  of  them  are  well  known  in 
consequence,  and  are  also  common  and  widely  distrib- 
uted, they  will  be  discussed  in  this  first  of  two  sections 
devoted  to  the  club  mosses. 

The  Commofi  Club-Moss. 

One  seldom  goes  far  in  the  scrubby  uplands  without 
coming  upon  the  long,  dark-green  stems  and  yellow 
spikes  of  the  common  club-moss  {Lycopodiuin  clavatuni), 
which  delights  to  grow  close  to  the  earth  and  half 
hidden  by  the  surrounding  vegetation.  In  sunny 
thickets,  however,  it  is  often  so  abundant  as  completely 
to  carpet  the  ground  for  many  yards  with  its  interlacing 
stems,  and  it  is  everywhere  one  of  the  most  abundant 
species  of  its  genus. 


82  THE  TRAILING  LYCOPODIUMS. 

The  main  stem  often  reaches  a  length  of  ten  feet  or 
more,  though  it  is  usually  much  shorter.  At  the  grow- 
ing end  it  is  usually  above  ground  and  covered  on  all 
sides  with  the  green  leaves;  at  the  opposite  end  it  is 
more  or  less  hidden  under  an  accumulation  of  dead  vege- 
tation, and  the  stems  and  leaves  are  yellowish.  Here 
and  there,  throughout  its  length,  single,  stout,  cord-like 
roots  are  given  ofT,  u^hich  extend  downward  until  they 
enter  the  soil,  where  they  usually  branch  once  or  twice. 
Frequently  this  main  stem  is  branched,  and  these 
branches,  like  the  axis  from  which,  they  spring,  main- 
tain a  course  parallel  with  the  earth.  At  short  intervals 
along  these  stems  other  branches  are  produced  which 
extend  upward.  During  the  first  year  they  are  from 
one  to  three  inches  long  and  are  simple,  but  at  the  next 
growing-season  they  add  more  to  their  length  and  at 
the  same  time  put  out  short  side  branches.  This  con- 
tinues for  several  years  until  the  older  branches  are 
several  times  branched,  with  occasional  roots  springing 
from  the  portions  nearest  the  earth.  There  is  thus  a 
regular  gradation  from  the  short  simple  branches  at  the 
growing  tip  of  the  stem,  less  than  a  year  old,  to  the 
larger  much-divided  branches  at  the  other  extreme 
which  have  outlasted  several  seasons. 

The  leaves  are  evergreen  and  persist  for  several  years. 
They  are  arranged  on  stem  and  branches  in  about  eight 
longitudinal  rows,  and  so  close  in  the  rows  as  to  over- 
lap. They  are  about  a  quarter  of  an  inch  long,  very 
narrow,  and  each  ends  in  a  long  soft  bristle.  On 
account  of  the  angle  at  which  they  are  set  on  the  stem, 
the  branches  appear  about  half  an  inch  in  diameter. 
The  edges  of  the  branch  leaves  are  entire  or  occasionally 
toothed ;    those   on  the  main    stems  have  larger  teeth. 


COMMON  CLUB-MOSS.     Lycopodiiim  clavatum. 


THE  TRAILING  LYCOPODIUMS.  83 

The  old  leaves  are  dark  green  in  colour,  but  the  new 
growth  is  light  silvery  green  and  very  noticeable  in 
early  summer.  Owing  to  a  slight  constriction  at  the 
place  where  each  season's  growth  begins,  it  is  very  easy 
to  ascertain  the  age  of  each  branch  by  counting  the 
constrictions. 

About  midsummer  the  plant  begins  to  put  up  its 
fruiting  parts.  These  are  simply  transformed  branches, 
and  often  indicate  the  relationship  by  producing  one  or 
more  sterile  branchlets  instead  of  the  usual  cones  of 
spores.  The  fruiting-spikes  are  always  borne  at  the 
tips  of  branches  of  the  previous  year,  in  the  position 
that  sterile  branches  hold  on  other  branch-tips  of  equal 
age.  The  fruiting  peduncles  are  most  abundant  on  the 
older  parts  of  the  plant,  but  any  branch  that  is  more 
than  a  year  old  may  produce  them.  Sometimes  in  a 
distance  of  a  single  foot  along  the  main  stem  there  will 
be  a  dozen  or  more  peduncles,  each  with  three  or  four 
strobiles,  or  fruit-cones,  at  the  summit. 

The  stalks  or  peduncles  are  from  three  to  eight  inches 
in  length,  the  average  being  about  five  inches.  They 
are  nearly  of  the  same  diameter  as  the  stem,  but,  owing 
to  the  absence  of  leaves,  appear  much  slenderer.  They 
are  clothed  with  appressed  bracts  like  the  leaves  in  out- 
line, but  which  are  smaller  and  at  maturity  are  yellowish 
in  colour.  The  strobiles  are  from  one  to  three  inches 
long,  thicker  than  the  peduncle,  and  consist  of  a  great 
number  of  close-set,  little  ovate  or  heart-shaped  sporo- 
phylls  with  thin  ragged  edges  and  soft  bristle  tips,  each 
covering  a  yellow  kidney-shaped  spore-case.  The  spores 
are  bright  yellow  and  are  produced  in  prodigious  quanti- 
ties. They, are  ripe  in  early  autumn.  The  lycopodium 
powder  of  the  shops   is  composed  of  the  spores  of  this 


84 


THE  TRAILING  LYCOPODIUMS. 


species,  the  supply  coming  mostly  from  Sweden,  Russia, 
and  Switzerland.  It  is  obtained  by  gather- 
ing the  spikes  just  before  the  spores  are 
shed,  and  collecting  the  powder  in  papers. 

Occasionally  a  form  of  this  species  is 
found  in  which  there  is  but  one  strobile 
on  each  peduncle.  This  has  been  named 
variety  inonostacJiyon.  It  is  usually  found 
in  dryish  situations,  and  its  form  is  appar- 
ently due  to  a  lack  of  some  of  the  normal 
plant's  requirements.  While  the  variety 
usually  produces  but  one  strobile  to  each 
spike,  it  is  possible  to  find  plants  with 
single  strobiles  near  the  growing  end,  and, 
farther  back,  peduncles  bearing  two  or  more 
strobiles, 

This  plant  is  one  of  those  in  greatest 
demand  for  holiday  decorations,  and  the 
demand  for  it  has  made  it  rare  in  many 
localities.  Fortunately,  owing  to  its 
manner  of  rooting,  the  whole  plant  is 
seldom  pulled  up,  and  the  fragments 
left  behind  may  ultimately  produce 
thrifty  plants,  so  that  it  is  likely  to  be 
a  long  time  before  it  entirely  disappears 
from  a  locality. 

This  is  the  club-moss  par  excellence, 
as  its  specific  name  indicates.  In 
America,  however,  it  is  better  known 
as  **  ground-pine,"  *' running-pine,"  or 
''trailing  Christmas  green."  Among  Old 
World  names  for  it  may  be  mentioned 
^^T*iLt:r"    "  fox-tail,"    "  stag-horn,"    '■  buck-horn," 


THE  TRAILING  LYCOPODIUMS.  85 

"buck  grass,"  and  ''wolf's  claw,"  all  of  which  doubtless 
have  reference  to  the  manner  in  which  the  branches  grow. 
In  Cornwall  it  is  known  as  "good-luck."  Other  names 
applied  to  it  in  various  localities  are  "  coral  evergreen," 
"  running-moss,"  "  snake-moss,"  "  toad-tail,"  and  "  lamb's- 
tail."  The  plant  has  strong  astringent  properties,  and 
was  once  used  in  medicine.  In  Sweden  the  stems  are 
woven  into  doormats  and  the  plant  is  known  as  "  matte- 
grass."  It  seems  to  have  been  the  custom  for  holiday 
parties  in  the  Old  World  to  trim  their  hats  with  the 
stems  of  the  club-moss.  The  Swedes  especially  are  men- 
tioned in  this  connection,  and  Wordsworth  alluded  to 
the  custom  in  the  following  lines : 

"  Or  with  that  plant  which  in  our  dale 
We  call  stag's-horn  or  fox's-tail 
Their  rusty  hats  they, trim. 
And  thus  as  happy  as  the  day 
These  shepherds  wear  the  time  away." 

This  species  is  one  of  the  most  widely  distributed  of 
its  genus.  It  is  common  in  the  Arctic  and  Sub-Arctic 
regions  of  both  Hemispheres,  and  has  also  been  reported 
from  tropical  America,  Brazil,  Cape  of  Good  Hope,  Mad- 
agascar, India,  Java,  New  Guinea,  the  Hawaiian  Islands, 
and  eastern  Asia.  As  might  be  expected,  there  is  con- 
siderable difference  in  the  appearance  of  specimens  from 
the  extremes  of  its  range,  and  it  is  a  question  whether 
they  are  all  varieties  of  one  species  or  a  series  of  closely 
related  species.  Many,  of  course,  have  been  described 
as  separate  species.  The  author  has  collected  specimens 
in  the  American  tropics,  which  are  almost  exactly  like 
our  common  form  except  that  they  are  more  luxuriant 
and  have  longer  peduncles.  In  North  America  it  ranges 
from    the    Arctic   Circle    southward    to    Oregon,    Iowa, 


86  THE  TRAILING  LYCOPODIUMS. 

Michigan,  Pennsylvania,  and  New  Jersey.  It  also  occurs 
in  the  mountains  of  North  Carolina.  In  the  southern 
part  of  its  range  it  may  be  expected  only  in  the  elevated 
regions.  Further  extensions  of  its  range  are  likely  to  be 
made  when  these  have  been  thoroughly  explored.  Its 
habitat  may  be  described  as  upland  woods,  but  it  is 
found  in  many  exposed  places  and  often  grows  in  old 
fields  and  pastures.  Its  abundance  makes  it  one  of  the 
first  species  likely  to  be  found  by  the  novice. 

The  Stiff  Club- Moss. 

If,  while  collecting  in  the  haunts  of  the  common  club- 
moss,  one  should  come  upon  a  plant  closely  resembling 
that  species  except  that  the  fruiting-cones  are  sessile  on 
the  ends  of  the  branches,  he  may  feel  sure  he  has  dis- 
covered the  St  iff  club-moss  (Zj't'^/^^^zV/ 7//  annotimuii).  This 
is  seldom  so  abundant  as  its  better-known  relative,  but  it 
is  by  no  means  rare  in  the  elevated  parts  of  the  northern 
United  States  and  Canada. 

The  species  is  like  Lycopodwui  clavatmn  in  so  many 
habits  and  superficial  features  that,  with  the  exception  of 
the  manner  of  fruiting,  one  description  would  almost 
serve  for  both.  The  main  stem  may  be  said  to  come 
nearer  our  idea  of  a  rootstock,  being  yellowish  for  most 
of  its  length,  less  leafy,  and  somewhat  more  deeply 
buried  in  the  debris  of  the  forest  floor.  In  length  it 
ranges  from  three  to  six  feet  or  more,  and  the  upright 
branches  are  usually  simple  the  first  season.  The  second 
season  they  branch  or  continue  to  increase  in  length, 
finally  reaching  a  height  of  twelve  inches  in  robust 
specimens,  and  often  three  or  four  times  forked.  The 
branches  appear  to  arise  dichotomously,  and  are  more 
nearly  erect  than  in  the  common  club-moss. 


STIFF  CLU3-M0SS.     Lycopodiuin  annotinum. 


THE  TRAILING  LYCOPODIUMS.  87 

The  leaves  are  about  a  quarter  of  an  inch  long,  some- 
what firmer  than  those  of  Lycopodiiun  clavatiiiii^  and  are 
arranged  on  stem  and  branches  in  from  five  to  eight 
rows.  They  are  narrowly  lanceolate  with  toothed  mar- 
gins, and  end  in  an  acute  point  without  a  bristle.  At 
the  ends  of  the  branches  the  tips  of  the  leaves  point  up- 
ward, but  below  this  they  are  more  spreading.  As  the 
new  season's  growth  springs  from  the  midst  of  the  erect 
leaves,  there  are,  in  consequence,  alternating  zones  on 
tlie  branches  in  wdiich  the  leaves  are  spreading  or 
appressed,  each  appressed  zone  marking  the  ending  of 
one  season's  growth  and  the  beginning  of  another.  From 
tliis  circumstance  the  plant  is  called  the  "  interrupted 
club-moss"  in  the  Old  World.  The  zones  are  most  notice- 
able in  specimens  growing  in  exposed  places.  Accord- 
ing to  Moore's  "  British  Ferns,"  old  branches,  after 
fruiting,  bend  over,  take  root,  and  start  new  rootstocks, 
but  there  appears  to  be  need  for  further  observation  on 
this  point  before  the  statement  is  accepted. 

The  chief  distinguishing  feature  of  this  species  is  found 
in  the  strobiles  or  fruit-cones.  They  are  half  an.  inch  to 
an  inch  or  more  long,  about  one  fourth  as  wide,  and  are 
borne  singly  on  the  tips  of  the  branches  with  no  sign  of 
the  peduncle  so  noticeable  in  Lycopodiiun  clavatuin. 
They  are,  as  usual,  made  up  of  a  great  many  small, 
closely  assembled  sporophylls,  yellow  in  colour  when 
ripe,  and  broadly  heart-shaped  with  an  irregular  margin 
and  slender  tip.  Each  subtends  a  kidney-shaped  spore- 
case  filled  with  pale  yellow  spores  which  are  ripe  in  late 
August  or  September. 

In  the  far  North,  and  on  mountain  tops  in  milder  re- 
gions, there  is  a  form  of  this  species  called  wdiYiQiy  puiigens. 
It  is  characterized  by  its  thicker,  shorter,  sharper  leaves 


8S  THE  TRAILING  LYCOPODIUMS. 

set  closer  on  the  branches  and  nearly  appressed  to  them. 
The  zones  marking  the  beginning  of  each  season's  growth 
are  also  very  clearly  marked.  It  is  in  all  ways  a  more 
compact  plant  than  the  type,  the  differences,  without 
doubt,  being  due  to  the  cold  and  exposure  to  which  it  is 
subjected. 

The  stiff  club-moss  is  found  from  Washington  to  Col- 
orado, Minnesota,  Michigan,  and  New  Jersey  to  Alaska 
and  Greenland,  appearing  to  be  very  common  in  suitable 
places  in  British  America.  It  also  occurs  in  the  colder 
parts  of  the  Old  World  and  in  the  Himalayas.  It  loves 
the  moist,  shady  woodlands,  and  is  seldom  plentiful  in 
the  dry  and  exposed  places  in  which  Lycopodmin  clava- 
tuin  thrives. 

"The   Ground-Pine. 

Although  several  lycopodiums  are  more  pine-like  in 
appearance,  the  name  of  ground-pine  is  most  often 
applied  to  the  plant  known  to  the  botanist  as  Lycopodium 
complaitatum.  It  would  require  a  lively  imagination  to 
detect  in  this  species  any  resemblance  to  the  pine,  for 
the  flat  branches  form  little  horizontal  fans  and  semi- 
circles quite  unlike  pine  needles  or  branches.  By  what- 
ever name  called,  however,  it  is  a  distinct  and  easily  recog- 
nized species,  while  its  abundance,  varied  habitat,  and 
extended  distribution  make  it  well  known  to  collectors. 

Like  the  common  club-moss,  the  ground-pine  has  a 
long  running  main  stem  or  rootstock  which  may  reach  a 
length  of  eight  or  ten  feet.  It  creeps  along  close  to  the 
earth,  or  an  inch  or  two  below  the  surface,  and  at  inter- 
vals sends  down  its  single  cord-like  roots.  The  branches 
are   erect,    those   of  the  season  being  from  two  to   five 


Lycopodiuin  annoiiniun  pungens. 


THE  TRAILING  LYCOPODIUMS. 


89 


inches  long  and  consisting  of  a  short  main  branch  termi- 
nating in  a  bud-like  point  with  a  pdir  of  opposite  fan-like 
lateral  branches  just  below  it.  These  lateral  branches 
fork  four  or  five  times  near  the  base,  or,  occasionally, 
nearer  the  tips,  the  terminal  branchlets  being  from  half 
an  inch  to  two  inches  long  and  spreading  out  horizon- 
tally in  flat  semi-circles.  Occasionally  there  is  a  single 
lateral  branch  near  the  base  of  the  main  stem.  The 
following  year  the  bud-like  point  carries  the  main  branch 
upward  a  few  inches  more,  and  there  produces  another 
pair  of  similar  forking  lateral  branches.  This  process 
may  be  repeated  for  several  years  in  succession,  resulting 
in  main  stems  a  foot  in  height.  The  lower  lateral 
branchlets  also  lengthen  more  or  less  in  subsequent  sea- 
sons by  additions  to  the  tips,  the  new  growth  being  very 
noticeable  at  midsummer  by  reason  of  its  lighter  colour. 
These  lateral  branches  may  also  send  up  short  branches 
like  the  main  one  the  second  season,  such  branches  aris- 
ing from  the  point  where  the  branchlets  are  given  off. 
The  branchlets  of  our  common  plant  are 
flattened  in  a  plane  parallel  to  the  earth, 
and  have  a  very  distinct  upper  and  lower 
side,  or,  in  other  words,  they  are  dorsi- 
ventral.  The  upper  surface  is  also  darker 
green. 

In  the  matter  of  leaves  this  species 
differs  greatly  from  most  of  our  native 
club-mosses.  First  of  all,  owing  to  the 
dorsi-ventral  branchlets,  there  are  two 
kinds  of  leaves  arranged  in  four  rows.  .yrFiS'orBranchLt. 
Extending  lengthwise  of  the  branchlets 
on  the  under  side  is  a  row  of  very  short  pointed  leaves  ; 
in  a  similar  row  on  the  upper  or  dorsal  side  is  a  series  of 


90  THE  TRAILING  LYCOPODIUMS. 

larger  leaves  with  tips  closely  appressed  ;  while  on  each 
edge  of  the  branchlets,  and  most  noticeable  from  above, 
is  another  row  of  the  large  leaves  with  slender  spreading 
tips.  The  largest  of  these  leaves  are  often  not  an  eighth 
of  an  inch  long,  but  their  bases,  being  broad  and  decur- 
rent,  form  a  tiny  lateral  wing  to  the  branchlets.  The 
leaves  on  the  main  stem  usually  have  narrower  bases. 

The  fruit-spikes  are  an  inch  or  more  long  and  are 
borne  on  slender  yellowish  peduncles  three  or  four  inches 
in  length.  These  are  produced  from  near  the  tips  of  the 
main  branches,  two  or  three  peduncles  from  each  branch, 
and  from  their  position  are  apparently  transformed 
lateral  brandies.  At  the  apex  each  peduncle  forks,  and 
each  fork  immediately  forks  again,  thus  giving  rise  to 
four  cones  of  fruit.  Occasionally  there  are  one  or  two 
more  fruit-cones,  but  four  is  the  usual  number.  The 
peduncles  are  sparsely  clothed  with  slender,  nearly 
appressed  scales,  and  the  cones  consist  of  large  numbers 
of  white-margined,  heart-shaped  scales  with  broad  bases 
and  slender  tips,  each  covering  a  kidney-shaped  spore- 
case  in  its  axil.  The  spores  are  very  numerous  and  are  ripe 
about  August  or  September.  Like  those  of  Lycopodmm 
clavatum,  they  are  gathered  in  quantity  and  have  a  com- 
mercial value.  In  most  club-mosses,  after  a  branch  has 
once  borne  fruit,  it  commonly  does  not  fruit  again,  but 
in  this  species  it  is  not  unusual  for  new  branchlets  and 
new  fruit-spikes  to  be  produced  for  two  or  perhaps  more 
successive  seasons. 

This  species  was  named  complanatum  by  Linnaeus,  and 
until  recently  our  well-known  plant  has  been  called  by 
that  name.  It  would  seem,  however,  that  the  branch- 
lets  in  the  Linnaean  specimens  were  less  inclined  to 
spread  horizontally,  and  from   this  circumstance  Mr.  M. 


GROUND-PINE.     Lycopodhim  coinphmatmn^ 


THE  TRAILING  LYCOPODIUMS. 


L.  Fenuild  thinks  our  plant  should  have  a  different 
name.  He  has  recently  proposed  to  call  it  V2^x\^'iy  flabel- 
lifonne.  There  seems  to  be  good  reason  for  thinking 
that  the  Linnaean  plant  is  represented  in  our  far  North* 
or,  rather,  that  our  plant  with  spreading  fan-shaped 
branches  tends  to  bear  these  branches  erect  as  one  pro- 
ceeds northward. 

Growing  with  the  common  ground-pine,  and  seldom 
distinguished  from  it  by  the  novice,  may  often  be  found 
specimens  in  which  the  branchlets  are  more  erect  and  in 
which  the  under  row  of  leaves  scarcely  differs  in  size  from 
the  upper  and  lateral  rows.  This  has  usually  been  regard 
ed  as  a  fairly  distinct  variety  or  species  named  chavicEcy- 
parisstis.  In  contradistinction  to  the  type,  the  main 
stem  is  quite  like  a  rootstock,  being  pale, 
slender,  and  buried  several  inches  in  the 
earth.  The  foliage  is  often  lighter  in 
colour,  and  the  branchlets  also  more 
inclined  to  lengthen  at  the  tips  the  second 
season  than  in  Lycopodiiun  coniplanatuDi^ 
and  while  they  are  not  spreading  they 
are  more  or  less  flattened,  as  in  the  other. 
The  fruiting  parts  are  exactly  like  those 
of  Lycopodiiun  coniplanatiun  but  are  said 
to  ripen  their  spores  two  or  three  weeks 
earlier.  This  latter  feature,  however, 
seems  to  depend  entirely  upon  the  soil  and 
surroundings  of  the  plant.  CJiamcEcy- 
parissiis  is  rarely  if  ever  found  growing 
alone,  and  the  invariable  proximity  of  specimens  of 
Lycopodiiun  coniplanatiun  suggests  that  it  is  only  a 
strong  and  well-marked  form,  due,  perhaps,  to  the  main 
stem  being  accidentally  covered  with  earth.     Intergrad- 


Lyco/>odiujn  coiii- 
planattiin  cluDiia'- 
cyparissus. 
Upper  and  under 
surface  of  Branchlet. 


92  THE  TRAILING  LYCOPODIUMS. 

ing  forms  often  occur.  Since  this  form  has  always  been 
known  in  American  publications  as  Lycopodiiim  com- 
planatiLin  chanicecyparissus,  it  is  called  by  this  name  here 
to  avoid  confusing  the  beginner.  An  older  name  for  it 
has  been  recently  unearthed,  and  if  one  is  inclined  to  call 
it  a  separate  species  it  should  be  named  Lycopodiiim 
tristacJiyon.  Tliose  who  consider  it  a  variety  or  form 
sliould  call  it  Lycopodiiim  complanatum  tristachyon.  The 
difficulty  experienced  in  raising  lycopodiums  from 
spores  prevents  the  application  of  a  f^^irly  decisive  test 
of  the  distinctness  of  these  two  forms.  If  it  could  be 
shown  that  from  th^  spores  of  one  form  tlie  other  may 
also  be  produced,  we  would  be  warranted  in  thinking 
them  forms  of  the  one  species. 

Lycopodiiim  complanatum^  like  the  common  club-moss, 
is  occasionally  found  with  fruiting-peduncles  bearing  a 
single  strobile  each.  This  form  has  been  described  as 
the  variety  Wibbei.  It  may  be  expected  in  localities 
where  the  type  abounds,  usually  in  the  more  sterile  and 
uncongenial  surroundings. 

This  species  is  used  in  great  quantities  for  decorations. 
It  is  said  that  the  trade  in  Christmas  greens  began  in 
New  Jersey  with  this  plant  more  than  half  a  century 
ago.  The  State  is  still  prominent  in  the  business, 
though  the  demand  long  ago  became  so  great  that  other 
sources  of  supply  had  to  be  found.  At  present  the 
supply  is  drawn  from  the  States  about  the  headwaters 
of  the  Mississippi,  more  than  two  hundred  tons  being 
gathered  each  year  from  a  single  State.  The  price 
realized  is  about  $75  a  ton.  In  consequence  of  the 
annual  raids  made  upon  it,  the  plant  is  rapidly  becoming 
rare,  but  small  patches  of  it  are  still  to  be  found  in  most 
localities,  while    in   some   remote   regions  it  still  carpets 


Lycopodiu]n  complanatiim  chamcccyparissus. 


THE  TRAILING  LYCOPODIUMS.  93 

the  ground  to  the  exclusion  of  all  else.  Because  of  its 
use  in  decorations  it  is  probably  oftener  seen  than  any 
other  species. 

Among  its  common  names  are  "  trailing  Christmas 
green,"  **  running-pine,"  **  ground-cedar,"  and  **  festoon 
ground-pine."  It  shares  the  name  of  "  creeping  jenny," 
with  the  common  club-moss,  and  is  also  known  as  '*  hog- 
bed  "  and  "liberty."  Occasionally  it  is  called  ''princess 
pine,"  but  this  name  belongs  by  right  to  one  of  the 
heathworts. 

The  ground-pine  is  found  in  the  North  Temperate 
Zone  of  both  Hemispheres  and  has  been  reported  from 
Madeira,  the  Azores,  Madagascar,  Java,  Sumatra,  New 
Guinea,  and  other  tropical  islands.  It  is  also  found  in 
the  Andes.  Some  of  the  forms  from  tropical  coun- 
tries are  very  different  in  appearance  from  ours  and  will 
doubtless  some  day  be  considered  distinct  species.  In 
North  America  the  plant  ranges  from  the  mountains  of 
Georgia  to  Labrador,  Iowa,  Washington,  and  Alaska. 
In  the  United  States  the  greater  part  if  not  all  of  the 
plants  belong  to  the  variety  flab  e  Hi  for  me.  As  Canada 
is  reached  it  fades  gradually  into  the  type.  The  range 
of  the  variety  chamcEcyparissus  is  usually  given  as  from 
Maine  to  Georgia  and  Minnesota,  but  it  will  probably 
be  found  to  be  coextensive  with  that  of  the  type  when 
it  is  better  known.  The  plant  loves  moist,  shady 
woodlands,  but  may  also  be  found  in  thickets  and 
pastures,  and  along  roadsides,  often  in  dry  situations, 
especially  in  upland  regions. 

The  Ground-Fir. 

In  the  northern  parts  of  our  continent  there  grows  a 
species  of  Ly  cop  odium  that  much  resembles  Lycopodiiim 


94  THE  TRAILING  LYCOPODIUMS. 

coinplanatiini  in  general  appearance,  and  which  is  as- 
sumed by  some  to  be  connected  with  it  by  the  form 
called  Lycopodiuin  coniplanatuin  chaina^cyparissiis.  While 
it  is  possible  that  cJiaincecyparisstis  may  represent  part  of 
tlie  line  along  which  its  evolution  proceeded,  it  is  cer- 
tainly a  distinct  species  now.  Botanists  know  it  by  the 
name  of  Lycopodiuin  alpimim,  and  the  general  public 
speak  of  it  as  the  ground-fir. 

The  ground-fir  resembles  its  congeners  in  having  a 
long  and  creeping  main  stem,  close  to  the  earth,  from 
which  at  short  intervals  it  sends  up  short,  erect  branches 
that  fork  repeatedly,  forming  dense,  flat-topped  clusters. 
As  in  tlie  other  species,  the  branchlets  add  to  their 
length  the  second  and  perhaps  subsequent  seasons,  the 
new  growth  usually  again  forking.  The  leaves  are  about 
an  eighth  of  an  inch  long,  broadly  lanceolate,  pointed, 
and  decurrent.  They  are  dark  green  in  colour,  thick, 
rounded  on  the  outer  surface,  and  closely  appressed  to 
the  branches,  along  which  they  are  arranged  in  four 
rows.  Owing  to  this  arrangement  of  the  leaves,  the 
branchlets  appear  four-sided. 

The  fruiting  parts  are  raised  above  the  flat-topped 
clusters  of  branchlets  on  very  short  peduncles 
which  are  manifestly  continuations  of  the  main 
branches,  and  which  resemble  the  branchlets  ex- 
cept that  they  are  less  leafy  and  the  leaves  are 
somewhat  narrower.  The  peduncles  usually  fork 
once  near  the  spikes,  and  the  leaves  gradually 
merge  into  the  short-pointed,  toothed,  and 
broadly  heart-shaped  sporophylls  of  the  spike. 
Branch  of  The  spikes  are  from  half  an  inch  to  an  inch  long, 

Lycopodiuin  ^ 

aij>inu7n.  cylindrical,    and  become    yellow-brown  with  re- 
flexed   sporophylls   when  aged.     The   peduncle   appears 


GROUND  FIR.     Lycopodium  alpimim. 


THE  TRAILING  LYCOPODIUMS.  95 

to  remain  green.  Among  the  majority  of  botanists  it 
is  customary  to  call  this  peduncle  a  branchlet,  and 
this  species  is  therefore  described  as  having  sessile 
spikes,  but  these  spikes  are  not  sessile  in  the  sense  that 
those  of  Lycopodiuvt  amiotimiin  are.  .  In  the  other  species 
it  is  evident  that  the  peduncles  are  transformed  branches, 
and  since  the  branchlets  that  bear  the  spikes  in  this 
species  differ  in  a  few  slight  particulars  from  those  that 
bear  only  foliage  leaves,  it  is  as  reasonable  to  call  them 
peduncles  as  branches. 

In  the  Old  World  this  species  is  sometimes  known  as 
"  heath  cypress."  It  was  once  used  in  dyeing  woollen 
goods  a  pale  yellow,  the  process  being  simply  to  boil 
the  goods  in  water  with  the  plant  and  some  leaves  of 
the  bog  whortleberry. 

Lycopodiiini  alpimnn  as  now  understood  ranges  from 
British  Columbia  to  the  Arctic  Circle,  being  common  in 
Alaska  and  Greenland.  It  is  also  found  in  the  North 
Temperate  Zone  of  the  Old  World,  extending  southward 
into  the  more  elevated  portions  of  Germany,  Switzer- 
land, and  Spain.  It  delights  in  the  open  spots  in  moun- 
tainous country,  but  in  the  colder  parts  of  its  range  may 
be  found  on  grassy  moors  near  sea-level. 

The  Savin- Leaved  Club-Moss. 

The  several  forms  or  species  of  Lycopodiiun  growing  in 
the  northern  part  of  North  America  have  given  botanists 
no  end  of  trouble  in  working  out  their  proper  relation- 
ships. They  are  all  more  or  less  like  Lycopodiuni  coin- 
planattim,  and  it  was  once  the  custom  of  students  to 
refer  them  all  to  this  species,  just  as  the  novice  would 
be  inclined  to  do  at  present.     It  was  less  than  ten  years 


96  THE  TRAILING  LYCOPODIUMS. 

ago  that  the  tendency  to  call  Lycopodium  coinplanaium 
chaimecyparissus  a  distinct  species  began,  and  a  still 
shorter  interval  has  elapsed  since  Mr.  Fernald  pointed 
out  the  differences  between  the  real  Lycopodium  com- 
planatum  and  our  common  form.  Lycopodium  alpinum^ 
while  much  like  these  in  general  appearance,  has  always 
had  some  standing  in  botanical  circles  as  a  distinct 
species,  though  even  in  several  editions  of  "  Our  Native 
Ferns"  Professor  Underwood  has  suggested  the  possi- 
bility of  its  being  another  form  of  Lycopodium  com- 
planatuin.  In  the  same  way  the  savin-leaved  club-moss 
{^Lycopodium  sabince folium)  has  often  been  thought  to  be  a 
form  of  Lycopodium  alpinum.  All  these,  however,  are 
now  believed  by  many  to  be  separate  species.  There  is 
no  doubt  that  they  are  all  closely  allied  to  Lycopodium 
complanaUim,  —  they  might  properly  be  called  the 
Lycopodium  complanatum  group  ;  but  with  a  series  of 
each  before  him  even  the  novice  would  have  no  trouble 
in  distinguishing  between  them.  Whether  the  differ- 
ences they  present  are  of  specific  value  depends  upon 
the  view-point  of  the  student.  The  forms  were  all 
named  long  ago,  and  are  not  therefore  new  segregates, 
but  the  tendency  in  the  past  has  been  to  ignore  them  as 
species. 

The  savin-leaved  club-moss  may  be  distinguished  from 
its  nearest  of  kin,  Lycopodium  alpinum^  by  the  fact  that, 
while  the  leaves  are  in  four  rows  as  in  that  species,  the 
branchlets  do  not  usually  appear  to  be  so  much  flat- 
tened. This  is  probably  due  to  the  fact  that  the  leaves 
of  Lycopodium  sabincBfolium  are  slightly  longer  and 
slenderer,  and  not  so  closely  appressed  to  the  stem. 
The  whole  plant  is  slenderer  than  Lycopodiuui  alpinum, 
but  it  has  the  same  trailing  habit  and  manner  of  growth. 


SAVIN. LEAVED  CLUB-MOSS.     Lycopodiim  sabincBfolium, 


THE  TRAILING  LYCOPODIUMS.  97 

The  most  striking  difference  between  these  two 
species,  however,  is  found  in  the  fruiting  portions.  In 
Lycopodiuui  alpinum  they  are  raised  somewhat  above  the 
foliage  on  thick  branch-like  stalks  with  appressed  leaves, 
but  in  the  present  form  they  are  borne  on  slender 
peduncles  two  or  three  inches  long,  which  bear  only 
scattered,  slender,  spreading  leaves.  In  Lycopodium 
alpimun  there  may  be  some  doubts  as  to 
whether  there  is  any  peduncle  at  all  to  the 
catkins  ;  but  no  doubt  whatever  exists  regard- 
ing their  occurrence  in  Lycopodium  sabince* 
foliinn.  The  spikes  are  an  inch  or  less  in 
length,  slender,  and  the  whorls  of  leaves  on 
the  peduncles  below  the  spike  have  the  odd 
trick  of  producing  sporangia.  When  the 
spores  are  ripe  the  sporophylls  are  usually  re- 
flexed  as  in  Lycopodium  alpinum.  The  cat- 
kins are    usually  borne  singly,    but  there    are      Branch  of 

.,  ,  -  T    '1  Lycopodiiim 

occasionally  two  or  three  together.  Like  sabtnce/oiiu7n. 
Lycopodium  complanatum,  the  old  branches  produce  new 
branchlets  and  new  catkins  for  at  least  two  years  in  suc- 
cession. 

The  savin-leaved  club-moss  is  named  for  its  resem- 
blance to  the  juniper  {Juniperus  sabind).  Its  range  is 
given  as  from  Prince  Edward  Island,  northern  New 
England,  and  Ontario,  northward.  In  geographical 
position  it  lies  between  Lycopodium  coinplanatui?i  and 
Lycopodium  alpinum,  and  the  three  may  not  improbably 
represent  three  strongly  marked  races  of  the  same 
species.  It  is  of  interest  to  note  that  while  Lycopodium 
alpinum  ranges  around  the  globe  in  high  latitudes, 
Lycopodium  sabincefolium  is  not  found  in  the  Old  World, 
although  there  is  a  variety  much  like  it  in  Japan  called 
Lycopodium  Nikoense, 


98  THE  TRAILING  LYCOPODIUMS. 

Lycopodium    Sitchense. 

Half  a  century  ago  Ruprecht  described  a  species  of 
club-moss  from  the  northern  part  of  North  America,  to 
which  he  gave  the  name  of  Lycopodium  Sitchense.  Until 
recently  little  attention  has  been  paid  to  this  plant, 
because  it  has  always  been  considered  a  variety  of 
Lycopodium  sabince folium.  It  differs  from  that  species  as 
at  present  considered  in  having  shorter  main  stems,  and 
shorter,  slenderer  branches  and  branchlets  which  form 
flat-topped  tufts  of  green  after  the  manner  of  Lycopodium 
alpinum.  The  branches  are  not  dorsi-ventrally  flattened, 
and  according  to  Underwood  the  leaves  are  arranged  on 
the  stem  in  five  rows. 

Lycopodium  Sitchense  is  the  smallest  and  most  delicate 
of  all  our  trailing  species.  The  main  stems  are  often 
less  than  a  foot  long  and  creep  on  the  surface  or  just 
beneath  it.  Its  leaves  are  very  slender,  about  an  eighth 
of  an  inch  long  ,and  thickly  set  on  the  branches,  from 
which  they  stand  out  in  a  way  that  faintly  suggests  the 
leaves  of  Lycopodium  obscurum.  As  in  all  the  other  trail- 
ing lycopodiums,  the  main  branches  con- 
tinue to  add  new  branchlets  for  several 
years. 

The  catkins  are  from  half  an  inch  to  an 
inch  long  and  an  eighth  of  an  inch  in 
diameter,  and  are  borne  on  slender  pedun- 
cles or  are  occasionally  sessile  on  the  ends  of 
the  branches.  Most  descriptions  of  this 
species  record  the  peduncle  as  less  than 
half  an  inch  long;  but  specimens  collected  in  the 
Province  of  Quebec  by  M.  L.  Fernald  have  peduncles 
nearly  two  inches  long,  and  this  feature  seems  to  be  not 


Lycopodium  Sitchense, 


THE  TRAILING  LYCOPODIUMS.  99 

uncommon.  When  peduncles  occur,  they  are  sparingly 
clothed  with  slender  bracts  that  are  nearly  like  the 
leaves  in  shape  and  size.  In  many  cases  but  a  single 
cone  is  borne  on  the  peduncle,  but  in  the  majority  the 
peduncle  forks  near  the  summit,  each  fork  ending  in 
a  cone.  At  maturity  the  sporophylls  appear  to  be 
reflexed. 

Lycopodijiin  SitcJicnsc  is  found  in  the  United  States  in 
Maine,  New  York,  Idaho,  and  Washington,  and  extends 
northward  to  Labrador  and  Alaska.  It  has  not  been 
half  a  dozen  years  since  its  claims  to  specific  distinction 
have  been  seriously  considered,  and  therefore  compara- 
tively little  is  known  about  it.  It  will  doubtless  be 
found  to  be  more  abundant  in  the  northern  tier  of 
States  than  it  has  thus  far  been  found  to  be.  Owing  to 
its  northern  habitat  it  is  likely  to  occur  upon  mountain 
tops  only  in  the  southern  parts  of  its  range. 

T'he  "Tree  Club-Moss. 

It  is  not  the  tree-like  proportions  of  the  tree  club-moss 
{Lycopodium  obscuriun)  that  have  suggested  its  common 
name,  but  rather  its  habit  of  growth  and  general  appear- 
ance. The  upright  stems  are  so  much  like  miniature 
pine  trees  that  any  one  finding  the  plant  for  the  first 
time  is  likely  to  identify  it  by  associating  its  appearance 
with  the  idea  suggested  by  the  common  name. 

The  tree-like  aspect  of  this  species  is  heightened  by 
the  fact  that  the  main  stem  is  deeply  underground,  and 
the  branches  arising  at  some  distance  from  one  another 
seem  to  be  different  plants  instead  of  several  branches  of 
one  individual.  Of  all  our  lycopodiums,  this  species  has 
a  main  stem  that  is  most  like  a  rootstock,  being  slender, 


loo  THE  TRAILING  LYCOPODIUMS. 

pale  in  colour,  sparsely  clothed  with  yellowish  scale-like 
leaves,  and  sending  out  roots  abundantly.  It  creeps 
extensively,  but  seldom  becomes  as  long  as  the  stems  of 
those  species  that  are  wholly  above  ground. 

The  principal  branches  rise  from  two  to  five  inches 
above  the  earth  before  producing  branchlets,  and  are 
covered  with  many  rows  of  curved,  slender  leaves  each 
about  an  eighth  of  an  inch  long,  but  decurrent  upon  the 
branches  in  such  a  way  as  to  appear  much  longer.  Each 
main  branch  produces  from  five  to  eight  alternate 
lateral  branches,  the  lowest  of  which  are  largest  and 
again  branched  two  or  three  times  before  the  final 
branchlets  are  produced.  The  branchlets  are  from  half 
an  inch  to  two  inches  long,  thickly  set  with  slender, 
almost  linear,  pointed  leaves  arranged  in  four  rows. 

Like  the  other  common  lycopodiums  this  species  con- 
tinues to  add  to  the  length  of  the  branches  for  several 
years,  during  which  the  main  branches  continue  to  rise 
and  put  forth  other  lateral  branches.  The  first  year 
these  latter  are  simple  or  slightly  forked  at  the  tips,  and 
the  next  year  the  new  growth  springs  from  these  tips, 
some  producing  one  and  some  two  branches.  During 
the  winter  the  leaves  become  a  light  yellow-green  in 
colour,  and  the  new  growth,  being  dark  green  with 
silvery  tips,  is  very  noticeable.  Branchlets  as  well  as 
branches  are  crowded,  half  erect,  and  in  old  specimens 
form  compact  tree-like  forms  nearly  a  foot  high. 

The  spikes  of  fruit  are  borne  singly  on  the  tips  of  the 
old  branches,  often  as  many  as  fifteen  spikes  on  a 
single  main  branch,  though  the  number  is  usually  much 
less.  The  spikes  are  cylindrical,  from  half  an  inch  to 
two  inches  or  more  in  length,  and  an  eighth  of  an  inch 
in  diameter.     The   sporophylls  or  scales  of  the  spike  are 


PLATE   IV.     TREE    CLUB- MOSS.     Lycopodium  ohscurum. 


CCPYRIGHT,    1905,    BY    FREDERICK    A      STOKES  COMPANY 


THE  TRAILING  LYCOPODIUMS.  loi 

broadly  heart- shaped,  with  a  slender  tip,  and  closely 
overlap.  Occasionally  the  spikes  are  prolonged  into 
leafy  branches  above,  showing  unmistakably  the  rela- 
tionship of  spikes  of  fruit  to  the  ordinar}^  branches. 
The  spores  are  ripe  about  September,  though  many 
ripen  later. 

Lycopodiiini  obsairtun  ranges  from  Newfoundland  to 
North  Carolina,  Tennessee,  Minnesota,  and  Montana. 
It  is  found  in  southern  Canada  and  extends  northward 
along  the  Pacific  to  Alaska.  It  prefers  moist,  shady 
woods,  and  is  one  of  the  common  species  of  the 
Eastern  States.  None  of  our  other  species  resemble 
it  very  closely,  which  makes  it  a  plant  easy  to  identify. 
This  is  another  of  the  species  used  for  holiday  decora- 
tions and  is  known  as  "  bunch  evergreen  "  or  *'  crowfoot." 


"The  Stag-Horn  Club-Moss. 

Nearly  all  the  club-mosses  in  our  flora  are  lovers  of 
the  north,  and  become  rare  as  soon  as  warmer  regions 
are  reached.  This  probably  accounts  for  the  fact  that 
the  great  State  of  California  has  not  a  single  species  of 
Lycopodiiini  within  its  borders.  The  Gulf  States  fare 
somewhat  better,  though  their  species  are  not  of  north- 
ern origin,  but  instead  are  northward  extensions  of 
tropical  species. 

The  rarest  of  the  tropical  club-mosses  within  our 
boundaries  is  the  stag-horn  club-moss  {Lycopodium  cer- 
nuuni),  which  barely  reaches  the  southern  parts  of  Missis- 
sippi, Alabama,  and  Georgia,  but  is  more  frequent  in 
Florida.  In  general  habit  it  is  like  the  tree  club-moss 
except  that  the  rootstock  or  main  stem  is  seldom  subter- 


I02  THE  TRAILING  LYCOPODIUMS. 

ranean.  The  aerial  branches  with  us  reach  a  height  of 
fifteen  inches  to  two  feet  and  are  erect  or  ascending. 
At  short  intervals  they  give  off  whorls  of  spreading 
lateral  branches  that  are  five  or  six  inches  long  and 
branch  again  repeatedly.  There  are  thus  formed  several 
nearly  level  circles  of  green  about  the  main  branches 
after  the  manner  of  the  wood  horsetail.  Should  the 
main  branches  become  decumbent  at  base,  the  lateral 
branches,  near  the  earth,  may  lengthen  and  become 
secondary  rootstocks.  The  main  stems  and  branches 
bear  large  numbers  of  spreading  leaves  an  eighth  of  an 
inch  or  more  long,  but  so  slender  that  the  stems  never 
seem  to  be  heavily  clothed.  The  branchlets  bear  great 
numbers  of  similar,  though  shorter,  spreading  leaves, 
which  give  the  plant  a  soft  and  airy  appearance. 

The  catkins  are  very  small,  often  no  more  than  an 
eighth  of  an  inch  long,  and  are  borne  at  the  ends  of 
the  branchlets,  from  which  they  droop  slightly.  The 
sporophylls  are  ovate,  tapering  to  a  slender  point,  with 
finely  ciliate  margins.  The  plants  are  very  fruitful,  and 
the  tall  stems,  with  their  circular  whorls  of  branches 
covered  thickly  with  the  small  cones,  make  a  very  attrac- 
tive picture. 

Lycopodiuin  cermiiun  is  pre-eminently  a  tropical  species. 
It  is  found  around  the  world  in  warm  latitudes,  and  ex- 
tends to  Japan,  Cape  Colony,  and  New  Zealand.  As 
might  be  supposed,  the  specimens  from  the  United 
States  are  undersized  plants.  In  favourable  situations 
it  often  grows  to  the  height  of  six  feet  or  more,  half 
supported  by  the  vegetation  in  its  vicinity.  The  cones 
may  also  reach  a  length  of  nearly  an  inch.  In  our  region 
the  plant  may  be  looked  for  on  moist,  half-shaded  banks, 
but  in  the  tropics  it  occasionally  grows  in  drier  situations. 


TREE  CLUB-MOSS.      Lycopodiuni  odscitrtun. 


STAG.HORN  CLUB-MOSS.     Lycopodium  cernuum. 


THE  TRAILING  LYCOPODIUMS.  103 

It  is  probable  that   it    will  yet    be   found  Louisiana, 

Texas  and  California. 

The  name  of  stag-horn  club-moss,'.,  stag-horn  moss, 
has  doubtless  been  given  this  species  in  allusion  to  the 
branches,  which  have  considerable  resemblance  to  the 
antlers  of  the  deer.  The  plant  does  well  in  cultivation 
and  is  common  in  conservatories. 


THE  ERECT  OR  DECUMBENT 
LYCOPODIUMS. 


THE  ERECT  OR  DECUMBENT 
LYCOPODIUMS. 


RITERS  on  the  fern  allies  usually  place  the 
lycopocliums  of  the  world  in  four  distinct 
sub-genera,    but    the    plants    are    all    so 
much  alike  that  no  botanist  ever  thinks 
of    considering    any    of   these     divisions 
as    separate  genera.     The  species  to  be 
presently   'treated    come    from    three    of 
these    sub -genera,  and    so    do    not 
form   a  natural  group  ;   but  since  all 
of  them  lack  the  long  trailing  stems 
of  the   other  species  it  will  be  con- 
venient to  consider  them  together. 

The  Shining  Club-Moss. 

On  deeply  shaded  hillsides,  where 
the  soil  is  rich  and  moist,  one  may 
often  discover  the  dark-green  and 
glossy  stems  of  the  shining  club- 
moss  {Ly  cop  0  din  111  liicidiiliini).  To 
such  localities  the  plant  clings  per- 
sistently in  spite  of  the  faUing  leaves 
and  shifting  particles  of  soil  that 
constantly  tend  to  bury  it.  Year 
after  year  its  growing  tips  struggle 


io8  DECUMBENT  LYCOPODIUMS. 

upward,  and  as  regularly  the  parts  at  the  other  extreme 
disappear  beneath  an  accumulation  of  debris.  It  is  ex- 
ceedingly rare  to  find  a  specimen  that  is  not  thus  half 
buried,  and  in  which  many  of  the  basal  leaves  are  not 
yellow  and  dead  in  consequence. 

The  stems  of  this  species  are  constructed  on  a  plan 
somewhat  different  from  that  of  the  trailing  species. 
There  is  neither  rootstock  nor  main  stem  in  the  usual 
sense,  but  instead,  the  whole  plant  may  be  likened  to 
one  of  the  primary  branches  of  Lycopodiiun  clavatuin. 
When  the  young  plant  begins  growth,  there  is  at  first  a 
single  short  stem.  At  length  this  forks  at  the  apex  into 
two  equal  branches,  and  these,  after  lengthening  from 
one  to  several  inches,  fork  like  the  original  stem,  this 
process  continuing  yearly  during  the  life  of  the  plant. 
The  stems  do  not  fork  every  year,  but  may  continue  for 
several  seasons  simply  adding  to  their  length.  Growth 
proceeds  very  slowly,  often  not  more  than  an  inch  a  year. 
The  stems  attempt  to  grow  erect,  but  after  some  years 
the  weight  causes  the  stem  to  become  decumbent  at  base, 
and  it  then  begins  to  decay.  In  the  meantime,  at  inter- 
vals along  the  old  stem,  strong  roots  have  been  sent 
down  into  the  soil,  and  when  this  decay  has  reached  the 
first  fork  there  are  thus  formed  two  separate  plants 
where  there  was  but  one  originally.  Subsequently  these 
two  become  four,  and  so  on,  a  single  plant  ultimately 
giving  rise  to  a  whole  colony.  The  living  plants  are 
often  five  or  six  times  forked,  but  the  majority  fork 
only  two  or  three  times. 

The  leaves  are  about  a  quarter  of  an  inch  long, 
narrowly  lanceolate  or  oblanceolate  and  sharp-pointed, 
the  outer  third  of  each  leaf  bearing  a  few  scattered  teeth 
on  the  margins.      They  are  thickly  set  on  all  sides  of  the 


SHINING  CLUB-MOSS.     Lycopodhnn  hicididum. 


DECUMBENT  LYCOPODIUMS.  109 

stem  and  stand  out  nearly  at  right  angles  to  it,  except 
those  at  the  tips  of  the  stems,  which  are  erect.  The  new 
and  spreading  growth,  springing  from  the  midst  of  the 
erect  leaves,  marks  the  stem  with  regular  zones  of 
spreading  and  appressed  leaves,  by  which  the  age  of  the 
plant  may  be  told.  On  old  parts  of  the  stem,  the  leaves 
are  usually  reflexed.  The  leaves,  though  short,  are  the 
largest  borne  by  any  North  American  species,  and  are 
further  distinguished  by  their  very  firm  texture  and 
dark-green  colour. 

The  spores  are  borne  in  kidney-shaped  sporangia,  one 
of  which  is  found  in  the  axil  of  each  of  the  ordinary 
spreading  leaves  near  the  tips  of  the  stems.  This  in 
appearance  is  a  wide  departure  from  the  usual  way  of 
fruiting,  but  when  one  considers  that  the  difference  is 
simply  that  in  fruiting  the  leaves  are  not  changed  in 
shape  and  colour,  a  fundamental  resem- 
blance is  easily  seen.  One  other  difference 
marks  the  fruiting  of  this  species, —  the  ends 
of  the  fruiting-branches  continue  to  grow, 
and  the  new  leaves  of  one  year  become 
the  spore-bearing  leaves  of  the  following 
season.  Thus  each  stem  has  in  time  several 
zones  of  sporangia.  In  some  cases  there 
are  at  least  six  of  these  zones.  The  spor- 
angia are  bright  yellow,  and  quite  noticeable  among  the 
green  leaves,  but  the  spores  do  not  appear  to  be  very 
abundant.  The  empty  spore-cases  often  remain  upon 
the  stems  for  years. 

In  addition  to  the  ordinary  means  of  reproduction  by 
spores  and  the  less  common  multiplication  by  the 
division  of  the  stem,  this  species  produces  numerous 
small  bulblets  that  are  capable  of   forming   new   plants. 


no 


DECUMBENT  LYCOPODIUMS. 


A  Bulblet. 


These  are  found  above  or  below  the  zones  of  sporangia 
and  issue  from  the  same  part  of  the  leaf  that  the 
sporangia  do.  Each  bulblet  is  borne  on  a  six-bracted 
stalk  barely  a  quarter  of  an  inch  long,  much  as  the  seed- 
pod  is  borne  in  flowering  plants.  The  bulblets  are  about 
as  long  as  their  stalks  and  appear  as  two  cotyledon-like 
scales.  Stalk  and  bulblet  have  been  likened  to  small 
plump   dustpans.     They   may   be   found   in   their  prime 

about    midsummer,    and    by 

early    autumn    they    have 

dropped    from    their    stalks 

and    begun    to    form     new 

plants.     They  may  be  easily 

found  by  searching  beneath 

the   old   plants.     The  stalks 

upon  which  the  bulblets  are 

borne  usually  continue  for  a    ^  Single  Spore-case. 
long  time    on  the    plants   and  may  often   be    found    in 
herbarium  specimens. 

This  species  is  sometimes  called  the  ''  hemlock  club- 
moss,"  from  the  resemblance  of  its  shiny  leaves  to  those 
of  the  hemlock  tree  {Tsuga  Canadensis).  It  is  also  called 
**  swamp  evergreen,"  in  allusion  to  the  moist  places  in 
which  it  loves  to  dwell.  It  is  extremely  tenacious  of  life. 
Specimens  have  been  known  to  continue  growth  for  a 
year  or  more  when  placed  in  a  vase  of  water  in  the 
house.  Most  of  the  club-mosses  are  very  difficult  to 
transplant,  but  this  species  takes  readily  to  cultivation. 

A  variety  of  club-moss  has  recently  been  described  by 
Professors  Lloyd  and  Underwood,  that  differs  from  this 
species  only  in  being  shorter  and  thicker  and  with 
slightly  narrower  leaves.  It  grows  in  the  same  manner 
as  does  the  better-known  plant,  produces  the  same  kind 


Lycopodiiini  porophilum. 


DECUMBENT  LYCOPODIUMS.  m 

of  bulblets,  and  appears  upon  examination  to  be  merely 
a  depauperate  form  of  Lycopodiiun  liicidiilum.  This  view 
of  the  matter  is  fully  borne  out  by  the  habitat  of  the 
plant,  for  it  is  described  as  growing  only  on  sandstone 
rocks.  It  is  only  to  be  expected  that  this  moisture-lov- 
ing species,  germinating  upon  a  dry  sandstone  rock, 
would  fail  to  come  to  its  full  luxuriance  if  it  lived  at  all. 
It  has  been  described  as  Lycopodiiun  porophiluni,  but 
seems  scarcely  worthy  of  even  subspecific  rank.  It 
would  more  properly  be  called  Lycopodiiun  lucidiiliiin 
porophiliun. 

Its  range  is  given  as  from  Wisconsin  to  Indiana,  Ken. 
tucky,  and  Alabama,  always  on  sandstone  rocks.  The 
discoverer  of  the  Kentucky  station  for  this  plant.  Miss 
Sadie  F.  Price,  author  of  "  The  Fern  Collector's  Hand 
Book  and  Herbarium,"  has  furnished  the  author  with 
specimens  of  this  form  and  with  the  drawing  which 
faces  page  no.  She  writes  that  she  collected  it  for  a 
dwarf  form  of  Lycopodiiun  luciduliun  and  that  when 
growing  it  looks  like  an  unthrifty  specimen  of  that 
species. 

Lycopodiiun  luciduliun  ranges  from  Newfoundland  to 
South  Carolina,  Alabama,  Iowa,  and  Minnesota.  Mr.  J. 
B.  Flett  has  recently  discovered  specimens  in  Washing- 
ton that  have  been  referred  to  this  species,  but  owing  to 
the  fact  that  the  leaves  are  thinner,  with  bluntish  tips 
and  fewer  teeth,  it  has  been  named  forma  occidcntale. 
Lycopodiiun  luciduliun  is  also  reported  from  Japan, 
China,  and  the  Himalayas.  It  does  not  seem  to  be 
known  in  Europe,  though  the  so-called  v?ix\^\.y  patens  of 
Lycopodiiun  selago  almost  exactly  matches  our  plant. 
Its  favourite  haunt  is  a  cool  springy  bank  in  the  dense 
shade  of  coniferous  trees,  though  it  may  also  be  found 


112  DECUMBENT  LYCOPODIUMS. 

in  drier  situations.     It  rarely   forms   large   patches,  but 
is  seldom  absent  from  suitable  localities  throufrhout  its 


The  Fir  Club-Moss. 

The  fir  club-moss  {Lycopodium  selago)  is  very  much 
like  the  shining  club-moss  in  general  appearance  ;  but 
the  collector  will  not  often  mistake  typical  specimens, 
for  the  reason  that  they  rarely  grow  in  company.  In 
the  United  States,  the  fir  club-moss  is  a  plant  of  high 
mountain  summits,  and  is  not  plentiful  until  British 
America  is  reached.  It  is  a  shorter  plant  than  Lycopo- 
diiim  liiciduhim  and  seldom  reaches  a  height  of  more 
than  six  inches.  The  stem  forks  several  times,  produc- 
ing close,  flat-topped  tufts  of  branches  that  are  usually 
erect,  but  in  old  or  thrifty  stems  may  become  decum- 
bent. Each  year  the  branches  add  to  their  length, 
though,  owing  to  the  short  seasons  in  its  haunts,  the 
annual  additions  are  not  very  great.  The  leaves  are  a 
little  more  than  an  eighth  of  an  inch  long,  crowded, 
narrowly  lanceolate  with  a  rather  broad  base,  and  are 
arranged  upon  the  branches  in  about  eight  rows.  They 
are  somewhat  concave  on  the  upper  side  and  curve 
upward  toward  the  apex  of  the  stem.  In  typical  plants 
the  edges  of  the  leaves  are  entire  and  the  apex  is  sharp- 
pointed. 

The  sporangia  are  borne  in  the  axils  of  the  leaves  as  in 
Lycopodiiim  lucidiihim,  but  although  they  are  no  smaller 
than  in  that  species  they  are  not  as  conspicuous,  owing 
to  the  upward-curving  leaves.  They  are  also  less  numer- 
ous. The  sporangia  are  not  found  on  stems  less  than 
one   season   old,  and,  since  they  persist  for  some  time, 


FIR  CLUB- MOSS.     Lye  op  odium   sclago. 


DECUMBENT  LYCOPODIUMS.  113 

several  zones  of  sporangia  may  be  found  on  a  single 
stem.  This  species  also  produces  gemmae  or  bulblets  in 
profusion,  and  propagation  by  that  means  is  probably 
more  common  than  by  spores. 

Until  recently  no  doubts  were  entertained  as  to  the 
specific  distinctness  of  Lycopodiiim  luciduluni  and  Lycopo- 
diiim  selago,  but  it  has  recently  been  asserted  that  as 
one  passes  downward  from  the  mountain  haunts  of 
Lycopodiiim  selago  he  may  find  forms  of  it  that  gradually 
merge  into  Lycopodiuiii  lucidtiluni.  It  is  therefore  sug- 
gested that  Lycopodiiim  selago  is  only  a  mountain  form 
of  our  common  species.  It  is  also  noticeable  that  in 
Europe,  where  Lycopodiiim  selago  is  common  and  Lycopo- 
diiim lucidiilum  unknown,  there  is  a  variety  with  spread- 
ing, toothed  leaves  that  appears  to  be  very  close  to,  if 
not  identical  with,  our  Lycopodiiim  liicidiiliim.  Some 
botanists  are  inclined  to  lay  stress  upon  the  fact  that  in 
Lycopodiiim  lucidiilum  the  zones  of  leaves  are  alternately 
appressed  or  spreading,  while  in  Lycopodiiim  selago  they 
are  all  appressed  or  at  least  ascending;  but  it  can  easily 
be  shown  that  the  alternating  zones  of  Lycopodiiim 
lucidiilum  are  due  to  longer  periods  of  growth,  the 
spreading  leaves  being  produced  at  the  height  of  the 
season.  If  only  a  few  leaves  were  produced  each  year, 
they  would  undoubtedly  be  ascending.  Should  further 
studies  prove  the  truth  of  the  theory  that  the  plants 
called  L^ycopodiiim  lucidiilum  and  Lycopodiiim  selago  are 
but  extreme  typjss  of  one  species,  a  rearrangement  of 
names  will  be  necessary.  Lycopodiiim  selago,  having 
been  named  first,  would  retain  its  name,  while  the  other 
would   become  Lycopodium  selago  luciduluni. 

This  species  was  once  valued  for  its  medicinal  quali- 
ties.    It  was  occasionally  used  as  an  emetic  and  cathar- 


114  DECUMBENT  LYCOPODIUMS. 

tic,  but  it  is  too  powerful  to  be  safe.  According  to 
Moore's  "  British  Ferns  "  it  was  also  used  in  the  form  of 
an  ointment  as  a  counter-irritant.  A  decoction  of  the 
stems  is  said  to  be  used  in  Sweden  to  destroy  vermin  on 
cattle.  Like  other  species,  this  plant  has  been  used  for 
dyeing  and  for  fixing  the  colour  of  woollen  goods.  In 
Ireland  it  is  known  as  "Virgin  Mary's  furze,"  and  in 
Cornwall  as  "  good-luck."  According  to  M.  W.  Gorman 
the  natives  of  Alaska  use  the  stems  to  produce  a  kind  of 
intoxication. 

In  the  United  States,  Lycopodium  sclago  is  found  from 
North  Carolina  to  Maine,  Michigan,  and  Washington, 
but  only  in  the  higher  mountains.  It  extends  to  Alaska 
and  Greenland,  being  most  plentiful  and  growing  nearly 
at  sea-level  in  these  northern  countries.  It  is  abundant 
in  northern  Europe  and  Asia,  and  has  been  reported 
from  Australia,  New  Zealand,  and  Antarctic  America. 
Many  forms  of  it  are  reported  from  the  tropics,  but  these 
are  probably  distinct  species. 


The  Bog  Club- Moss. 


The  club-mosses  with  which  the  average  collector  is 
most  familiar  delight  in  moist  spots  in  woodland,  on 
mountain  side,  or  on  moor,  but  the  bog  club-moss 
{Lycopodium  inundatiun)  is  so  fond  of  moisture  that 
it  frequently  grows  in  beds  of  sphagnum  close  to  the 
trembling  boggy  margins  of  our  small  Jakes  and  ponds, 
its  habitat  alone  being  often  sufficient  to  identify  it. 

The  stems  of  this  species  present  still  another  depar- 
ture from  the  more  familiar  club-moss  form.  They  are 
slender  and  threadlike,  from  two  to  eight  inches  long, 
and  are  rooted  near  the  base,  beyond  which  they  usually 


BOG  CLUB-MOSS.  Lycopodium  imindatiun, 
(Twice  natural  size.) 


DECUMBENT  LYCOPODIUMS.  115 

rise  clear  of  the  earth,  bending  over  in  the  form  of  an 
arch  to  root  again  at  the  tip.  The  plant  is  therefore  as 
truly  a  walking  club-moss  as  Cainptosoriis  rhizopJiyllus 
is  a  walking  fern.  In  the  smaller  specimens  the  stems 
commonly  do  not  branch,  but  in  the  larger  ones  two  or 
three  short  branches  may  be  produced,  each  of  which 
roots  at  the  tip  like  the  main  stem.  Indeed,  this  is  their 
only  means  of  continuing  existence,  for  at  the  end  of  the 
growing  season  the  older  parts  of  the  plant  die,  leaving 
these  vigorous,  bud-like  tips,  filled  with  plant-food,  as  so 
many  points  from  which  new  stems  may  be  produced 
the  following  year. 

The  leaves  are  from  an  eighth  to  a  quarter  of  an  inch 
long,  linear,  entire,  with  broad  bases  and  pointed  tips, 
and  are  closely  crowded  on  all  parts  of  the  stem,  though 
owing  to  its  horizontal  position  those  on  the  under  side 
turn  upward,  so  that  all  appear  to  grow  from  the  upper 
side.  The  fruiting  parts  are  at  the  tips  of  separate 
stems  which  are  much  like  the  main  stems  except  that 
they  are  stiffly  erect.  They  are  quite  short,  usually 
under  five  inches  high,  and  spring  from  the  older  parts 
of  the  main  stem.  They  are  clothed  with  leaves  similar 
to  those  on  the  other  parts  of  the  plant,  but  less  spread- 
ing, and  there  is  usually  but  one  fruit-stem  to  a  plant. 
The  cone  of  fruit  is  from  a  quarter  of  an  inch  to  two 
inches  long  and  about  twice  the  diameter  of  the  stem. 
There  is  no  sharp  line  marking  the  separation  between 
stem-leaves  and  sporoph}lls,  one  almost  imperceptibly 
merging  into  the  other.  Typical  sporophylls  are  broad 
and  rounded  at  base,  toothed  above,  and  suddenly 
narrowed  to  a  long  slender  tip  ;  but,  near  the  base  of  the 
spike,  sporangia  are  borne  by  the  ordinary  linear  stem- 
leaves.     The  sporangia  approach  globose  in  shape,  and 


ii6  DECUMBENT  LYCOPODIUMS. 

though  but  one  is  borne  in  the  axil  of  each  sporo- 
phyll  they  are  numerous  enough  to  make  the  spike 
the  heaviest  part  of  the  plant.  The  spores  are  ripe 
in  late  autumn. 

A  larger  form  of  this  plant,  with  slender  branching 
stems  and  slightly  longer  leaves,  has  been  named  the 
variety  Bigelovii.  According  to  Baker's  *'  Fern  Allies  " 
the  fertile  stems  of  this  are  sometimes  a  foot  long,  with 
a  spike  six  inches  in  length.  It  is  the  author's  opinion, 
however,  that  a  form  of  the  closely  related  Lycopodiiun 
alopeairoidcs  has  been  wrongly  identified  as  this  form. 
He  has  seen  no  specimens  of  the  so-called  variety 
Bigelovii  that  were  not  more  properly  placed  elsewhere. 

In  localities  where  the  bog  club-moss  is  undisturbed, 
the  plants  frequently  form  *'  fairy  rings  "  like  those  formed 
by  various  fungi.  The  rings  are  due  to  the  creeping 
habit  of  the  plant,  which  tends  to  carry  the  tips  slowly 
outward  from  the  centre,  which  is  left  vacant  by  the 
dying  of  the  older  parts.  Where  the  progress  is  unob- 
structed, the  circles  continue  to  enlarge   for  many  years. 

The  bog  club-moss  is  a  northern  plant,  being  plentiful 
in  Labrador  and  Alaska,  and  extending  southward  to 
New  Jersey,  Pennsylvania,  Illinois,  and  Washington.  It 
is  also  a  common  species  in  the  north  of  Europe.  It  is 
seldom  found  except  in  swampy  ground,  and  is  con- 
sidered rather  rare  in  the  United  States.  After  the 
Carolina  club-moss  it  is  our  smallest  species.  It  is  possi- 
ble to  find  fruiting  specimens  less   than  two  inches  long. 

The  Fox-Tail  Club-Moss. 

Just  as  the  bog  club-moss  begins  to  be  rare  southward, 
another  species  appears  which   resembles  it  so   closely 


/f'^-^/'-Hr 


FOX-TAIL  CLUB-MOSS. 
Lycopodhun  alopeciiroides.     One -third  natural  size. 


Lycopodium  alopecuroides  adpressum. 


DECUMBENT  LYCOPODIUMS.  117 

that  the  novice  might  be  excused  if  he  should  think  it  a 
gigantic  specimen  of  the  northern  plant.  This  new  spe- 
cies is  the  fox-tail  club-moss  (^Lycopodiiini  alopeciLroides\ 
a  plant  which  reaches  its  best  development  in  the  South- 
ern States,  but  which  in  the  northern  part  of  its  range  is 
still  so  robust  that  the  single  characteristic  of  size  is 
nearly  enough  to  distinguish  it. 

The  sterile  stems  of  Lycopodiiun  alopeciiroides  are  from 
ten  inches  to  two  feet  long.  In  small  specimens  they 
may  arch  as  do  those  of  Lycopodiiun  immdatuiii,  but  in  the 
larger  plants  they  are  likely  to  be  simply  trailing.  The 
main  stems  are  about  an  eighth  of  an  inch  in  diame- 
ter and  give  off  several  lateral  branches,  the  more  vig- 
orous of  which  may  branch  again.  The  stems  root  most 
abundantly  near  the  tips,  but  may  also  produce  slender 
roots  wherever  they  come  in  contact  with  the  soil. 

The  leaves  are  a  quarter  of  an  inch  or  more  in  length 
and  are  produced,  thickly  on  all  sides  of  the  stem,  but 
those  from  the  under  surface  grow  upward  and  appear  as 
if  produced  from  the  sides.  They  are  narrowly  linear, 
spreading,  with  the  tips  pointed,  and  the  margins  bear- 
ing an  occasional  slender  tooth. 

The  fruiting  stems  are  erect,  a  foot  or  more  high,  and 
are  clothed  with  appressed  or  spreading  leaves  like  those 
of  the  sterile  parts.  The  spore-bearing  area  is  from  one 
to  four  inches  long,  and  about  one  third  thicker  than  the 
stem  ^which  bears  it.  The  sporophylls  are  much  like 
the  ordinary  leaves,  but  longer  and  with  more  teeth. 
The  spores  ripen  very  late  in  the  year,  often  not  until 
the  end  of  October  in  the  north.  Unlike  Lycopodium 
inundatum,  a  single  plant  often  produces  several  fer- 
tile stems,  as  well  as  certain  additional  upright  stems 
that  are  ma;nifestly  in   the   nature  of   fertile   stems,  but 


iiS  DECUMBENT  LYCOPODIUMS. 

which  never  come  to  fruition.  These  hitter  are  borne  on 
the  branches  or  on  the  newer  parts  of  the  main  stem,  and 
are  doubtless  produced  too  kite  in  the  season  to  be  fruit 
ful.  In  exposed  places  throughout  its  range  there  is 
found  growing  with  the  type  a  form  that  by  some  has 
been  considered  a  species  and  named  Lycopodium 
adpressum.  It  differs  from  the  type  in  being  somewhat 
smaller,  with  shorter,  thicker,  less  spreading  leaves, 
and  with  slender  fruiting-stems  clothed  with  appressed 
leaves  in  shape  like  those  of  the  sterile  stems.  The  fruit- 
spikes  are  from  one  to  four  inches  long,  and  about  twice 
the  diameter  of  the  stems  that  support  them,  the  sporo- 
phylls  being  rather  broader  at  base  than  in  the  type. 
Owing  to  the  appressed  leaves,  the  fruiting  parts  are 
more  distinct  and  cone-like  than  those  of  the  type. 
The  spores  are  produced  in  great  abundance.  Sev- 
eral fertile  stems  are  usually  produced  on  each  plant, 
and  the  upright  sterile  stems  noticeable  in  the  typical 
Lycopodiuin  alopecuroides  are  also  plentiful.  All  the  char- 
acteristics in  which  this  form  differs  from  typical  plants 
are  such  as  might  be  produced  by  an  unusual  amount  of 
light  and  heat,  and  the  exposed  situations  in  which  the 
plants  grow  seem  fully  to  account  for  this  appearance. 
Under  these  circumstances  it  seems  better  to  call  this 
a  sub-species  and  to  name  it  Lycopodiuin  alopecuroides 
adpressum.  Although  this  form  has  always  been  known 
by  the  name  oi adpressum,  whether  treated  as  a  species  or 
as  a  variety,  it  has  recently  been  proposed  to  change  it  to 
CJiapmani,  because  the  name  adpressum  was  earlier  ap- 
plied to  another  plant.  If  considered  as  a  variety,  our 
plant  would  now  be  called  Lycopodium  alopecuroides 
Chapmani. 

A   curious    form  of   adpressum  was    found  on    Staten 


^■"1 

^ 

I  ^B 

■i    T 

3r  ^ 

PLATE  V.     LYCOPODIUM    ALOPECUROIDES   ADPRESSUM. 


CCPirRnHT,   ;905,   BY    FREtEBICK    A.   STCKES  CCV 


DECUMBENT  LYCOPODIUMS.  119 

Island,  New  York,  by  W.  II.  McDonald,  who  named  it 
polyclavatum.  It  is  like  ordinary  adprcssum  with  the 
exception  that  the  fertile  stems  each  bear  from  two 
to  six  short  branches,  some  of  wdiich  produce  fruit  cones 
while  others  are  sterile. 

Still  another  form  of  Lycopodiiuji  alopeairoidcs  is  occa- 
sionally considered  a  distinct  species  and  called  Lyco- 
podiiun  pinnatum.  It  is  a  slender  plant,  growing  in 
wet  places,  and  derives  its  specific  name  from  the  sup- 
position that  its  stems  are  pinnately  branched.  It 
is  certain,  however,  that  while  the  stems  may  appear 
pinnate  they  are  not  really  so,  and  that  this  is  simply  a 
more  branched  form  of  the  species.  Aside  from  this 
character  the  stem  is  long  and  slender,  and  the  leaves 
are  inclined  to  stand  out  at  right  angles  to  the  stem, 
this  being  due  to  the  w^atery  habitat  the  form  affects. 

Lycopodiiun  alopecuroides  is  essentially  a  tropical  plant 
and  within  our  limits  is  confined  rather  closely  to  the 
Atlantic  and  Gulf  coasts.  In  South  America  it  is  said 
to  extend  to  Monte  Video.  The  typical  form  extends 
northward  to  Long  Island,  where  it  was  first  discovered 
by  the  author  near  Babylon.  The  form  pinnatum  is  a  lux- 
uriant phase  of  the  plant  found  only  in  watery  situations 
in  the  Gulf  States.  Lycopodiiun  alopecuroides  adpressiun 
extends  to  the  coast  of  Massachusetts  and  is  the  common- 
est form  from  New  Jersey  to  Virginia.  The  plant  is  a 
lover  of  the  swampy  sand-barrens  and  often  covers  large 
areas.  So  far  as  known,  both  the  species  and  varieties 
are  absent  from  the  interior  of  the  continent. 

The  various  disguises  of  this  plant  have  always  been  a 
puzzle  to  botanists.  It  was  first  described  as  a  variety 
of  Lycopodiiun  inundatuni,  and  when  the  forms  were 
discovered  they  too  were  named  as  varieties.     There  is 


120  DECUMBENT  LYCOPODIUMS. 

no  doubt,  however,  that  it  is  distinct  from  Lycopodiuni 
iinindaium.  The  common  name  of  '*  fox-tail  club- 
moss  "  has  been  given  this  species  in  allusion  to  the 
bushy  spike  of  fruit  like  a  fox's  tail. 

"The  Carolina  Club-Moss. 

The  Carolina  club -moss  {Lycopodiuni  Carolinianuui) 
is  one  of  the  most  diminutive  of  its  race,  and  its 
claims  to  being  the  smallest  North  American  species 
could  not  be  contested  with  any  prospects  of  success  by 
any  save  the  bog  club-moss.  In  the  northern  part  of  its 
range,  at  least,  it  is  clearly  entitled  to  the  honour,  and  it 
is  only  when  we  include  the  more  robust  plants  of  the 
South  that  any  doubts  arise. 

The  sterile  stems  of  this  species  are  from  one  to  four 
inches  long  and  are  appressed  to  the  earth,  clinging  so 
closely  by  means  of  numerous  roots  that  the  plant  can 
scarcely  be  got  up  entire  without  the  use  of  knife  or 
trowel.  Owing  to  their  position  the  stems  are  markedly 
dorsi-ventral,  and  the  leaves  are  of  two  sorts,  the  larger 
often  a  quarter  of  an  inch  long,  borne  on  the  sides  of 
the  stem  and  spreading ;  the  others  awl-shaped  and 
borne  on  the  upper  side  of  the  stem.  The  large  leaves 
are  ovate-lanceolate  with  a  broad  base,  entire  margins, 
and  pointed  apex.  In  these,  one  side  is  longer  than  the 
other,  causing  them  to  curve  sidewise  and  throwing  the 
tiny  midrib  a  little  to  one  side  of  the  middle.  Although 
so  short,  the  stems  usually  produce  one  or  two  small 
spreading  branches. 

The  (ruiting-stems,  of  which  there  appears  to  be  but 
one  to  a  plant,  no  matter  how  robust  the  specimen,  rise 
from  the   older  portion  and  often  reach   a  height  of  ten 


CAROLINA  CLUB-MOSS.     Lycopodinm  Caroliniamun, 


DECUMBENT  LYCOPODIUMS.  121 

or  twelve  inches,  —  several  times  the  length  of  the 
sterile  stems.  They  are  very  slender,  but  are  stiffly 
erect  and  sparsely  clothed  with  small,  linear,  appressed, 
long-pointed  leaves.  At  the  top  is  borne  the  single 
cone,  consisting  of  many  close-set,  yellow  sporophylls, 
each  subtending  a  roundish  spore-case.  The  sporophylls 
are  broad  and  rounded,  with  spreading  tips,  and  the 
cone  is  about  three  times  the  diameter  of  the  stem  or 
peduncle.  In  the  northern  part  of  its  range  the  fertile 
stems  are  usually  short,  and  the  cones  are  from  half  an 
inch  to  an  inch  long.  In  the  South  the  stems  are  taller, 
and  the  fruiting  portion  often  three  or  four  inches  long, 
though  not  much  thicker  than  in  the  Northern  plant. 

The  Carolina  club-moss  is  found  from  central  New 
Jersey  south  to  Florida  and  Louisiana,  so  far  as  known, 
only  near  the  coast.  It  delights  in  open  sandy  swamps 
in  the  pine-barrens,  and  in  its  New  Jersey  haunt  is  fre- 
quently a  neighbour  of  that  rare  little  fern,  ScJiizcea 
pusilla.  It  is  not  found  in  Europe,  but  according  to 
Baker's  ''  Handbook  of  the  Fern  Allies "  it  occurs  in 
Ceylon,  Hong  Kong,  New  Guinea,  Tasmania,  and  the 
Cape  of  Good  Hope.  It  is  also  reported  to  occur  in 
South  America  as  far  south  as  Brazil.  It  is  probable 
that  many  of  these  forms  will  ultimately  turn  out  to  be 
different  species.  Some  are  described  as  having  stems  a 
foot  long.  In  the  tropics,  forms  referred  to  Lycopodimn 
Carolinianuni  sometimes  bear  tubercles  on  the  sterile 
stems. 


THE  PSILOTACE/E, 


THE  PSILOTACE^. 

NE  of  the  most  curious  of  all  the  fern 
allies,  and  one  of  the  rarest  in  our  flora, 
is  that  relative  of  the  lycopodiums 
which  botanists  call  Psilotmn  triqiietruin. 
This,  in  fact,  is  often  considered  as 
one  of  the  Lycopodiaceae,  and  in  many 
books  will  be  found  included  as  one  of  the  four  genera 
supposed  to  belong  to  that  family  ;  but  the  typical 
Psilotum  form  is  so  different  from  that  of  Lycopodium 
that  in  the  opinion  of  modern  botanists  we  are  war- 
ranted in  placing  the  species  in  a  separate  family  which 
has  been  named  the  Psilotaceae.  In  this  family,  as  now 
recognised,  there  is  the  single  genus  Psilotmn,  and  in 
this  genus  less  than  half  a  dozen  species.  Baker's  "  Fern 
Allies "  names  but  two  species  and  several  varieties. 
Others  are  inclined  to  give  some  of  the  most  pronounced 
of  these  varieties  specific  rank,  but  in  any  event  the 
genus  will  always  remain  with  very  few  species.  The 
family  being  so  small,  a  descrip.tion  of  our  single  species 
will  sufifice  for  an  account  of  the  whole  family. 

Like  many  of  its  relatives  among  tropical  lycopo- 
diums, our  species  {^Psilotum  triqiictruiii)  is  epiphytic  and 
usually  grows  on  the  trunks  of  trees,  though  it  is  occa- 
sionally found  upon  the  earth,  on  fallen  logs,  or  the  like. 
The  mature  plant  has  no  true  roots,  from  which  it  is  con- 
jectured  that   it    is   a  saprophyte,  like  the  mushrooms, 


26 


THE  PSILOTACE/E 


absorbing  its  nourishment  from  decaying  plant  tissues  by 
means  of  its  root-like  rhizomes.  These  rhizomes  are  curi- 
ous structures  consisting  of  a  great  number  of  cord-like 
organs  that  form  a  tangled  mass  from  six  inches  to  a  foot 
or  more  in  extent.  From  various  parts  of.  the  rhizome 
the  stems  rise  to  a  height  of  twelve  inches  or  more,  at  the 
top  forking  repeatedly  to  form  the  fan-shaped  branches. 
The  base  of  the  main  stem  is  about  one  tenth  of  an  inch 
in  diameter  and  is  three-angled,  and  the  branchlets  are 
three-winged.  The  leaves  are  reduced  to  tiny  linear 
scales  less  than  one  twelfth  of  an  inch  long,  and,  though 
scattered  along  the  angles  of  the  stems 
and  branches,  are  so  inconspicuous  that 
the  plant  always  appears   to  be  leafless. 

The  sporangia  occur  singly  along  the 
branchlets,  each  small  leathery  spore-case 
held  in  a  slight  hollow  of  the  stem  by  a 
forked  sporophyll  which  looks  like  a  pair 
of  the  stem  leaves.  The  spore-cases  are 
globular  or  top-shaped,  three-lobed,  three- 
celled  affairs,  opening  at  the  top,  when 
ripe,  by  three  tiny  oblong  slits.  Spore- 
cases  of  this  type  are  often  called  synan- 
gia.  From  their  appearance  they  have 
been  likened  to  .tiny  apple-dumplings, 
the  spore-cases  are  produced  in  abundance 
and  the  spores  are  numerous,  the  plant  has  additional 
means  of  reproduction.  When  it  grows  in  soil,  it  may 
send  out  certain  slender  subterranean  shoots  which  pro- 
duce a  great  many  buds  or  bulblets  by  which  the  plant 
multiplies  rapidly.  Occasionally  these  buds  may  re- 
main dormant  for  a  long  time.  The  prothallia  of  this 
species  is  unknown. 


Although 


r  SI  latum  triquet)-um. 


THE  PSILOTACE^.  127 

The  range  of  Psilotuin  triqiictruin  is  from  northern 
Florida  southward.  The  species  was  once  reported 
from  South  Carolina,  but  some  doubt  may  be  enter- 
tained as  to  its  existence  there  at  present.  In  central 
Florida  it  is  not  uncommon,  usually  growing  on  the 
palmetto,  and  it  is  probable  that  it  may  yet  be  dis- 
covered in  other  of  the  Gulf  States  near  the  coast.  It  is 
widely  spread  in  the  tropics,  extending  quite  around  the 
world  and  reaching  Japan  and  New  Zealand.  It  has 
long  been  known  under  the  specific  name  of  triquetruui 
in  allusion  to  its  three-angled  branches,  but  recent  works 
occasionally  list  it  as  Psilotuin  uudiiin,  Campbell,  in 
his  "  Mosses  and  Ferns,"  is  inclined  to  add  to  the 
Psilotaceae  the  genus  Tincsipteris,  which  contains  a  single 
species  growing  in  New  Zealand.  Other  authors  place 
this  with  the  Lycopodiaceae.  No  fossil  plants  have  yet 
been  found  that  can  with  certainty  be  referred  to  the 
Psilotaceae,  though  various  specimens  from  the  Coal 
Measures  are  commonly  regarded  as  belonging  to  this 
family. 


THE  SELAGINELLACE/E,  OR  DWARF 
CLUB-MOSSES. 


THE  SELAGINELLACE^. 


y  N  the  time  of  Linnaeus  the  plants  that  are  now 
referred  to  the  genus  Selaginella  were  thought  to 
be  true  club-mosses,  and  such  species  as  were 
then  known  will  be  found  in  old  botanical  works 
in  the  genus  Lycopodhnn.  There  is,  however, 
this  important  difference  between  them.  In  the 
lycopodiums  the  spore-cases  bear  many  spores  all 
of  the  same  size  and  appearance,  which  produce 
ia    of    one    kind,  while    in  Selaginella  the  lower 

spore-cases  in  the  fruit-spikes  each  bear  about  four  large 

spores    called  megaspores,  while  the  spore-cases  higher 

up   in   the  spike  bear  great   numbers  of  smaller  spores 

called    microspores.     When  the  microspores   germinate 

they  form  very  reduced  prothallia  bearing  only  anther- 

idia,  and  are  therefore  called  male  prothallia;  while  the 

megaspores  produce  larger    prothallia 

with  only  archegonia,  and    hence    are 

called    female    prothallia.     Both    sorts 

of  prothallia  begin  to  develop  before 

the  spores  have  left  the  sporangia,  but 

even  after  the  spores  have  fallen,  the 

prothallia,  unlike  those   of  most  of  the    Megaspore  of  Seiagt. 

ferns    and     fern      allies,    never     leave  '^'^^^'^;;;£';^;?;/^"'^^ 

the  spores.     When  the  prothallium  in 

the  megaspore  has  nearly  attained  its  growth,  the  thick 


132 


SELAGINELLACE^. 


and 


rough 


walls  of  the  spore  split  apart  at  the  apex, 
exposing  the  part  of  the  prothallium  bearing  the  arche- 
gonia,  and  these,  after  fertilization,  contain  the  develop- 
ing plants.  On  account  of  the  early  development  of  the 
prothallium,  and  various  other  features  connected  with 
the  manner  of  spore  production,  the  selagi- 
nellas  are  thought  by  many  students  to  be  more 
nearly  related  to  the  flowering  -  plants  than 
are  any  other  Pteridophytes.  The  fertile  spikes 
differ  very  little  from  the  flowers  of  the  pines 
and  their  allies.  The  most  noticeable  distinc- 
tion is  that  the  microspores  of  the  pines  (called 
pollen)  are   borne    in    separate  catkins. 

In  most  other  respects  the  selaginellas  have  a 
general  resemblance  to  the  lycopodiums,  but 
except  in  tropical  countries  this  is  is  not  close 
enough  to  be  confusing.  Our  North  American 
species  are  easily  distinguished  by  their  much 
smaller  size ;  in  fact  they  are  so  diminutive 
that  they  are  much  likelier  to  be  confused  with  the 
mosses  than  with  the  lycopodiums. 

In  our  species  the  main  stems  seldom  reach  a  length  of 
more  than  six  inches.  Often  they  are  trailing,  but  occa- 
sionally they  are  more  erect.  The  trailing  species,  as  in 
the  lycopodiums,  send  out  forking  roots  at  frequent 
intervals,  but  the  species  with  upright  stems  root  only 
near  the  base.  The  stems  are  usually  branched,  though 
not  dichotomously  so,  and  the  whole  plant  is  generally 
very  close  to  the  earth. 

The  leaves  are  minute  and  very  abundant,  clothing 
both  stems  and  branches.  The  form  of  the  leaves  has 
been  made  the  basis  for  dividing  the  genus  into  two 
sections.     In  one  they  are  all  alike  and  arranged  in  many 


Spike  of 
Selaginella. 


PLATE  VI.     ROCK    SELAGINELLA.      Sclaginella  rupesttis. 


CCPYRIGHT,    1905,    BY    FREDERICK    A.    STOKES   COMPANY 


SELAGINELLACE^e. 


^33 


rows,  and  in  the  other  they  are  of  two  forms  and 
arranged  in  four  rows.  Of  these  four  rows,  two  contain 
large  leaves  and  two  contain  small  ones.  The  large 
leaves  are  in  the  two  rows  on  the  sides  of  the  stem, 
while  the  small  ones  are  on  the  up- 
per side  of  the  stem  and  alternate 
with  them. 

The  fruit  is  borne  at  the  ends  of 
the  branches,  a  spore  -  case  in  the 
axil  of  each  leaf.  In  some  species 
the  fertile  spikes  are  hardly  to  be 
distinguished  from  the  ordinary 
branches,  while  in  others  the  spore- 
of  Sa^ineHa  bearing  leaves  are  yellowish  in 
Leaves.  colour,  morc  or  less  changed  in  n^ 
shape,  and  are  assembled  in  little  cones  as 
in  most  lycopodiums.  Often  these  cones  are 
distinctly  four -sided.  The  sporangia  are 
nearly    spherical    and    open     transversely    at  Leaf  of 

,  T-i  •  -if-^i^-  Selaginella 

the  apex.      1  he  species  mamly  fruit  late  in         rupestris. 

,  -^  (Enlarged.) 

the  year. 

There  are  nearly  four  hundred  species  of  Selaghiella 
known  to  science,  the  great  majority  being  found  in  the 
tropics,  where  their  size  and  abundance  render  them  a 
conspicuous  part  of  the  undergrowth  in  woods  and  on 
moist  banks.  In  our  region  they  are  usually  so  small 
and  moss-like  as  to  be  easily  overlooked.  The  plants 
from  the  warmer  parts  of  the  world  are  often  character- 
ised by  a  delicacy  in  form  and  colour  that  causes  them 
to  be  in  great  demand  for  cultivation  in  conservatories 
nearer  the  Poles.  Several  of  them  are  climbing  species. 
The  famous  resurrection-plant,  or  resurrection-moss,  sold 
under  various  other  names  to  the  curious,  is  a  species 
of  Sclagiiiclla. 


k 


134  SELAGINELLACE>E. 

The  name  Sclaginclla  is  a  diminutive  of  Sclago,  the 
ancient  name  of  one  of  the  lycopodiums  which  our 
species  greatly  resemble.  Formerly  the  quillworts 
(Isoetes)  were  united  with  the  genus  Selaginclla  to 
form  the  Selaginellaceae,  but  as  they  are  regarded  at 
present  they  not  only  form  a  distinct  family,  but  are 
included  in  another  order.  The  Selaginellaceae,  there- 
fore, may  be  said  to  consist  .of  the  single  genus  Sclagi- 
nclla, 


Key  To  The  Selaginellas. 


I. —  Leaves  narrow,  all  alike  .  ,  .  ,  . 

Stems  pendant,  rooting  throughout.     Western 

S.  Orega7ia 
Stems  erect,  rooting  at  base  only.      Western 

S.  Bigelovu 
Stems  creeping  and  tufted  .... 

Branchlets  under  /s  of  an  inch  long.     Western 

S.  cinerascens 
Branchlets  longer    ..... 
Leaves  tipped  with  a  point.     Western 

►S".   Watsoni 
Leaves  tipped  with  a  white  bristle 

Leaves  closely  appressed.      Southern 

5.  arenicola 
Leaves  somewhat  spreading.     Eastern 

5".  rupestj-is 
Fertile  stems  larger  than  the  sterile.     Northern 

5.  spinosa 
II, —  Leaves  broader,  of  two  sizes  .  ,  ,  . 

Plants  weak,  trailing,  rooting  throughout 

Fertile  spike  roundish,  leafy  .  5.  apiis 

Fertile  spike  four-sided.     Western      .S'.  Dmiglassi 
Plants  slender,  erect  or  ascending.     Southern 

S.  Liidom'ctana 
Plants  stout,  densely  tufted,  rooting  only  at  base 

Leaves  obtuse,  awnless        .  S.  lepidophylla 

Leaves  awn-tipped  .  ,        S.  Pri7iglei 


THE  TRUE  SELAGINELLAS,  OR  SELA- 
GINELLA  RUPESTRIS  GROUP   " 


THE  SELAGINELLA  RUPESTRIS 
GROUP. 


botanists  consider 
at  the  shape,  size, 
d  arrangement  of  the 
leaves  of  Selaginella  are 
of  sufficient  importance 
to  warrant  the  separa- 
tion of  this  genus  into 
four  sub-genera.  The  first  of  these  is  called  Euselagineiia 
and  contains,  those  species  with  leaves  all  alike  and  ar- 
ranged in  many  rows.  From  the  fact  that  the  common 
species  in  eastern  North  America  are  typical  of  this 
group,  they  are  often  spoken  of  as  the  Selaginella  rn- 
pestris  group.  Although  here  called  the  true  selagi- 
nellas  they  are  relatively  few  in  number,  probably 
less  than  twenty-five  in  all,  though  distributed  very 
widely  over  the  earth. 


T^he  Rock  Selaginella* 

The  student  of  the  mosses  is  likely  to  be  better 
acquainted  with  the  haunts  of  the  rock  selaginella, 
( Selaginella  rupestris )  than  the  student  of  the  fern 
allies  himself,  for  it  is  a  species  of  the  dry  ledges 
and  mossy  boulders,  growing   in  situations  shunned  by 


I40  THE  SELAGINELLA  RUPESTRIS  GROUP. 

others  of  its  kin,  and  so  small  as  to  be  easily  overlooked 
unless  one  is  on  a  special  hunt  for  it.  One  who  has 
once  seen  it,  however,  will  seldom  overlook  it  again,  for 
the  whole  plant  has  a  characteristic  grey-green  colour  not 
common  to  mosses,  that  is  sure  to  catch  the  eye  and 
make  recognition  at  some  distance  possible. 

The  main  stems  of  this  species  are  from  one  to  five 
inches  long  and  nearly  prostrate.  From  these  issue 
great  numbers  of  secondary  branches,  several  times 
forked,  but  all  so  short  that  the  topmost  branch  does 
not  reach  a  height  of  three  inches.  The  plants  grow  in 
communities,  with  branches  so  intertwined  that  the 
individuals  are  dif^cult  to  distinguish,  the  whole  form- 
ing a  dense  little  mat  that  often  covers  an  area  of  several 
square  feet. 

The  leaves  are  arranged  in  about  eight  ranks,  and  so 
close  together  upon  the  stems  and  branches  as  to 
completely  cover  them.  At  the  tips  of  the  branches 
they  are  more  or  less  spreading,  but  elsewhere  they  are 
rather  closely  appressed.  They  are  frequently  described 
as  less  than  a  sixteenth  of  an  inch  long,  but  in  vigorous 
specimens  they  may  reach  more  than  twice  this  length, 
exclusive  of  the  awn-like  tip.  They  are  narrow,  with  a 
deep  groove  on  the  back,  and  taper  from  the  base  to  the 
rounded  apex.  Each  leaf  bears  a  slender  white  bristle 
at  the  tip,  which  is  one  third  to  one  half  the  length  of  the 
leaf.  It  is  these  white  bristles  among  the  green  that 
give  the  peculiar  greyish  colour  to  the  plant.  The 
leaves  also  bear  numerous  cilia  on  the  margins,  and  the 
bristles  also  have  very  short  ones. 

The  fertile  spikes  are  similar  to  ordinary  branches  in 
appearance,  the  most  noticeable  differences  being  that 
they  are  erect  and  distinctly  four-sided.     Thesporophylls 


ROCK  St  LAG  IN  ELLA.     Selaginclla  ritpcstris. 


THE  SELAGINELLA  RUPESTRIS  GROUP. 


141 


differ  from  the  ordinary  foliage  leaves  only  in  being 
broader  at  base  and  having  rather  more  numerous  cilia. 
They  are  arranged  in  four  ranks,  a  row  on  each  of  the 
four  angles  of  the  spike,  with  the  bases 
closely  over-lapping.  The  spikes  are  from 
half  an  inch  to  an  inch  long.  After  the 
spores  have  fallen,  the  sporophylls  be- 
come reflexed,  and  the  sporangia,  split 
nearly  into  halves,  spread  out  in  the  axils 
like  small  greenish  flowers.  The  megas- 
porangia  are  supposed  always  to  bear 
four  megaspores,  but  all  four  do  not 
always  develop.  They  are  bright  orange 
yellow  in  colour  and  are  large  enough  to 
be  seen  with  the  unaided  eye.  They  are 
borne  so  plentifully  by  this  species  that 
they  are  often  noticeable  on  the  ground 
about  the  plants  late  in  autumn.  The 
megaspores  and  microspores  are  said  to 
be  borne  in  the  same  leaf  axils. 

Until  a  few  years  ago  Selaginclla  rupcstris  was  consid- 
ered to  be  a  widespread  though  somewhat  variable 
species.  Recently,  however,  it  has  become  the  fashion 
to  describe  each  form  as  a  distinct  species,  no  matter 
what  its  characteristics,  and  about  forty  of  these  forms 
have  been  so  described.  It  can  scarcely  be  dou'bted 
that  the  species,  as  once  regarded,  covered  too  great  a 
range  of  forms  ;  but  it  is  equally  certain  that  many  of 
the  newly  described  species  are  mere  forms  due  to  con- 
ditions of  environment.  The  points  most  relied  upon 
for  separating  them  are  the  presence  or  absence  of  the 
bristle  tips  of  the  leaves  and  the  number  of  cilia  on  the 
leaf  margins.     Only  the  more  noteworthy  forms  can  be 


Spike  of  Rock 
Selagfinella. 
(Enlarged.) 


142  THE  SELAGINELLA  RUPESTRIS  GROUP. 

treated  here.  The  student  who  wishes  to  make  further 
investigations  is  referred  to  the  article  by  Dr.  Hierony- 
mus  in  the  volume  'of  Hedwigia  for  1900.  A  synopsis, 
with  a  key  to  the  American  forms,  was  published  in  the 
Fern  Bulletin,  Volume  10,  1902. 

A  form  from  the  mountain  tops  of  North  and  South 
Carolina,  in  which  the  awns  on  the  tips  of  the  leaves 
are  longer  and  twisted,  was  long  ago  described  as  a 
species  and  named  Selaginella  tortipila.  It  is  more„com- 
monly  called  a  variety.  A  plant  allied  to  this,  but  with 
stems  more  erect,  is  the  variety  SJierivoodii  {Selaginella 
Sheriuoodii,  Underwood.)  Still  another  form  from 
the  coastal  plain  of  the  Carolinas  and  Georgia  has  been 
named  Selaginella  acanthonoia.  It  differs  from  typical 
Selaginella  rupestrisxn  having  about  twelve  cilia  along  the 
dorsal  groove  in  the  leaves  and  is  probably  best  consid- 
ered a  variety  and  called  Selaginella  rupestris  aeanthonota. 
A  densely  tufted  form  from  western  Nebraska  and 
Montana  is  the  variety  densa  {Selaginella  densa,  Rydberg). 
A  form  with  lax,  less  crowded  leaves,  and  shorter  awns, 
has  been  reported  from  Colorado  and  New  Mexico  as 
the  variety  Fendleri.  Plants  from  New  Mexico  and 
Arizona  with  smaller  megaspores  and  less  angular  fertile 
spikes  is  the  variety  riipincola  (Selaginella  rupineola. 
Underwood). 

In  Baker's  '^  Handbook  of  the  Fern  Allies "  the 
range  of  Selaginella  rnpestris  is  given  as  *'  North  and 
South  Temperate  zones  of  both  the  Old  and  New 
worlds,  also  on  the  Andes,  Himalayas,  and  mountains  of 
Brazil  and  Ceylon."  In  the  early  editions  of  Under- 
wood's "  Our  Native  Ferns  "  it  is  recorded  as  growing 
from  "  New  England  to  Florida,  Texas,  California,  and 
northward."     In  the  latest  edition  of  the  latter  book  its 


THE  SELAGINELLA  RUPESTRIS  GROUP.  143 

range  is  given  as  "  New  England  and  Ontario  southward 
to  Alabama  and  westward  to  California  and  British 
Columbia,"  —  this  latter  probably  being  nearly  correct 
for  .our  part  of  the  world.  It  shows,  however,  how 
greatly  the  idea  concerning  this  species  has  changed 
within  ten  years. 

Selagiiu'lla  riipestris  is  usually  found  on  dry  rocks,  and, 
,  in  the  Eastern  States  at  least,  appears  to  have  a  pref- 
ferehce  for  granite,  gneiss,  and  mica  schist.  It  is  exceed- 
ingly irregular  in  distribution,  being  abundant  in  some 
sections  of  its  range  and  extremely  rare  in  others.  In 
the  vicinity  of  New  York  it  is  a  common  species  and 
may  be  found  in  the  public  parks  as  well  as  on  a  large 
number  of  the  rocky  outcrops  in  the  surrounding  country. 
It  is  likeliest  to  be  found  in  thin  soil  on  the  tops  of  the 
ledges,  and,  being  an  evergreen  species,  is  most  easily 
found  in  early  spring.  This  species  is  sometimes  called 
"  grey  moss." 


Selaginella  Watsoni. 


The  plant  recently  named  Selaginella  Watsoni  may  be 
recognised  at  once  by  the  fact  that  it  looks  like  a 
luxuriant  form  of  Selaginella  rupestris.  The  leaves 
are  rather  larger  and  thicker  than  in  Selaginella  rupes- 
tris, with  few  or  no  cilia,  and  end  in  a  short,  pale 
green  awn.  Owir.g  to  the  colour  of  the  awn  and 
the  scarcity  of  cilia,  tlie  plant  has  a  tinge  of  deeper 
green  than  is  found  in  the  common  plant  of  the  East. 

The  main  stems  are  from  four  to  six  inches  long, 
nearly  prostrate,  and  produce  strong  roots  throughout 
their  length.  The  fertile  spikes  are  an  inch  or  more 
long  and  sharply  four-angled.     This  species  is  a  plant  of 


144 


THE  SELAGINELLA  RUPESTRIS  GROUP. 


elevated  regions  and  is  found  only  in  the  West.  It  has 
been  reported  from  various  peaks  in  Utah,  Nevada,  and 
California,  always  at  altitudes  above  5,000  feet.  A  form 
very  similar  to  this,  but  differing  in  having  about  eight 
cilia  on  the  leaf-margins  and  no  awn  tips  to 
the  leaves,  has  been  described  as  a  species 
under  the  name  of  Selaginella  niutica.  The 
\\^  fact  that  the  sporophylls  usually  have  a  short 
awn-tip  seems  to  indicate  that  it  is  a  form  of 
Selaginella  Watsoni,  and  this  is  further  borne 
out  by  its  habitat  in  the  mountains  of  Colo- 
rado, New  Mexico,  and  Arizona.  We  would 
therefore  call  it  Selaginella  Watsoni  niutiea,  and 
give  its  range  as  high  mountains  from  Colorado 
to  New  Mexico  and  California. 


Brancli  of 
Selaginella 

Watsoni. 
(Enlarged.) 


The  Sand-Barren    Selaginella. 

It  is  almost  certain  that  the  sand-barren  selaginella 
{Selaginella  arenieola)  and  the  common  species  of  the 
Northeastern  States,  sprang  from  the  same  stock  ; 
but  the  former  has  lived  so  long  in  the  sandy  wastes 
that  border  the  Gulf  of  Mexico  that  its  appearance  has 
been  greatly  changed  in  consequence.  Possibly  there 
may  yet  be  found  intergrading  forms,  but  the  typical 
plant  is  so  distinct  in  appearance  that  it  is  properly  con- 
sidered a  separate  species.  This  species  is  an  excellent 
illustration  of  the  adaptation  of  plants  to  their  surround- 
ings. It  grows  in  exposed  sandy  places,  and  accordingly 
its  leaves  are  narrow,  plentifully  ciliated,  and  appressed 
closely  to  the  stem,  partly  in  an  effort  to  avoid  excessive 
transpiration,  and  partly,  no  doubt,  to  protect  its  green 
cells  from  the  strong  light. 


Selaginella  Bigelovii. 


THE  SELAGINELLA  RUPESTRIS  GROUP. 


145 


The  stems,  under  the  influence  of  the  intense  insola- 
tion, are  nearly  erect,  but  seldom  become  more  than  two 
inches  hi^h.  They  are  densely  tufted,  much  branched, 
and  form  compact  little  mats  on  the  sand.  From  the 
part  nearest  the  earth,  slender  branching  roots  descend 
into  the  soil,  and  in  the  search  for  moisture  extend  for 
long  distances,  being  often  three  times  the  length  of 
the  aerial  parts  of  tlie  plant.  The  leaves  are  smaller 
than  those  of  any  of  our  other  selaginellas,  and  those  on 

the  sterile  stems  are 
not  distinguishable 
from  one  another  by 
the  unaided  eye. 
Under  a  lens  they 
are  seen  to  be  very 
narrow,  with  a  whitish 
awn  at  the  apex  and 
many  minute  cilia  on 
the  outer  edges, while  the  usual  channel 
runs  lengthwise  of  the  outer  side.  They 
are  thickly  clustered  on  the  stems  and 
branches,  and  so  closely  appressed  that 
stem  and  leaves  combined  have  a  diam- 
eter of  about  a  thirty-second  of  an 
inch.  The  fruiting-spikes  are  very 
numerous  and  terminate  the  ends  of 
the  branches.  Although  the  whole 
plant  is  usually  under  three  inches 
high  these  fertile  spikes  may  reach  a 
length  of  an  inch  or  more.  They  are 
sharply  four-angled,  with  a  diameter  somewhat  greater 
than  that  of  sterile  branches.  The  sporophylls  are  much 
larger    than    the  leaves    and    are    borne    in   four    closely 


SAND-BARREN  SELA- 
GINELLA. 

Seia  tri'fi  clla  a  re  n  icola . 


146  THE  SELAGINELLA  RUPESTRIS  GROUP. 

imbricated  rows,  one  row  on  each  angle  of  the  spike. 
They  are  often  triangular  in  outline,  broad  at  base,  and 
end  in  a  short  awn.  The  margins  bear  abundant  cilia 
that  are  so  small  as  not  to  be  easily  seen.  The  megaspo- 
rangia  are  especially  abundant  and  bright  yellow  in 
colour,  quite  distinguishable  without  a  lens. 

The  sand-barren  selaginella  has  thus  far  been  reported 
from  Florida,  Louisiana,  and  Texas,  but  it  is  likely  to 
be  found  in  suitable  situations  in  any  of  the  sand-bar- 
rens along  the  Gulf  coast.  Its  slender,  cylindrical,  grey- 
green,  erect  stems  will  be  easily  identified  when  found. 
It  was  originally  described  ^s  Selaginella  arenaria. 

Selaginella   Bigelovii.     - 

In  the  days  when  it  was  customary  to  refer  everything 
at  all  resembling  Selaginella  rupestris  to  that  species,  it 
was  described  as  having  stems  from  six  inches  to  a  foot 
long.  The  plant  that  is  nowadays  called  Selaginella 
rupestris  is  much  smaller,  and  at  its  best  does  not  reach 
the  minimum  length  quoted.  An  explanation  of  the 
discrepancy  is  found,  however,  when  we  take  into  con- 
sideration one  of  its  forms  recently  named  Selaginella 
Bigelovii.  In  this  the  stems  ordinarily  reach  a  length  of 
six  or  eight  inches,  and  in  vigorous  specimens  are,  of 
course,  still  longer. 

It  is  likely  to  surprise  the  beginner  to  learn  that 
Selaginella  Bigelovii  was  ever  referred  to  Selaginella 
rJipesiris.  Aside  from  its  long  stems,  its  habitat  and 
manner  of  growth  are  sufficiently  different  to  separate  it. 
It  is  an  erect  or  ascending  species,  with  stems  that  pro- 
duce roots  only  near  the  base.  For  some  distance 
above  the  soil,  the  stems  are  commonly  unbranched,  or. 


Selaztnella  cinerascens. 


THE  SELAGINHLLA  RUPESTRIS  GROUP.  147 

if  branched,  the  branches  may  be  considered  essentially 
like  the  main  stems.  Toward  the  apex  the  stems  are 
pinnate,  with  short,  alternate  branches,  the  lowest  from 
one  to  three  inches  long  and  increasing  in  length  to  the 
summit.  These  lateral  branches  are  branched  in  the 
same  way  as  the  main  stem,  and  their  branches  are  again 
divided,  the  ultimate  branchlets  rarely  reaching  the 
length  of  half  an  inch.  The  leaves  are  narrowly  linear, 
slightly  channelled  down  the  back,  with  numerous  cilia 
on  the  margins  and  a  short  white  awn  at  the  apex. 
They  are  small,  numerous,  and  closely  appressed  to  the 
very  slender  branches.  Those  on  the  main  branches  are 
usually  light  brown,  the  rest  being  dark  green.  The 
fertile  spikes  are  fairly  plentiful  and  usually  occupy  the 
places  of  lateral  branchlets  a  short  distance  from  the  tips 
of  tlie  branches.  The  cones  are  from  a  quarter  to  half 
an  inch  long,  and  quadrangular,  the  sporophylls  being 
rather  triangular,  short,  pointed  at  the  apex,  ciliated  on 
the  margins,  and  slightly  eared  at  the  base.  The  fruit 
may  be  found  on  the  plant  at  all  seasons  of  the  year. 

Selaginclla  Bigelovii  is  found  in  southern  California 
only,  but  there  it  is  not  an  unconvmon  species.  It  grows 
in  the  foothills  at  altitudes  up  to  about  '3,000  feet,  and 
prefers  half-shaded  clay  soil  or  the  cliinks  of  rocks. 
Like  many  of  the  mosses  and  ferns  in  this  region,  its 
chief  period  of  growth  is  in  the  rainy  or  winter  season. 
At  other  times  it  becomes  dry  and  brittle,  but  revives  at 
the  next  rainy  season. 

Selaginella  Cinerascens. 

Selaginella  cinerascens  is  another  of  the  segregates  of 
Selaginella  rupestris  that  has  been  described  so  recently 


148  THE  SELAGINELLA  RUPESTRIS  GROUP. 

as  to  have  no  common  name.  In  general  appearance  it 
is  most  like  Selaginclla  Bigehvii,  but  may  be  at  once  dis- 
tinguished from  that  species  by  the  fact  that  it  is  a  pros- 
trate plant  rooting  from  all  parts  of  the  stem. 

In  robust  specimens  the  main  stems  may  reach  a 
length  of  six  inches  or  more,  but  they  are  usually  shorter. 
These  stems  are  pinnately  branched,  the  branches  short 
and  rather  numerous.  From  these  branches  still  smaller 
branches,  about  a  quarter  of  an  inch  long,  arise,  and 
upon  these  are  usually  borne  a  pair  of  branchlets  so 
small  as  to  be  mere  spurs,  which,  with  the  branch-tip, 
form  a  figure  suggestive  of  the  qox\mc\\\.\o\-\3\  Jleur-de-lis 
design.  All  parts  of  the  plant  are  covered  with  leaves, 
those  on  the  main  stems  being  closely  appressed,  and 
those  on  the  branch-tips  more  spreading.  The  leaves 
are  rather  broadly  linear,  acute  or  rounded  at  the  apex, 
with  a  suggestion  of  a  terminal  awn,  and  with  few  or  no 
marginal  cilia. 

The  spikes  are  short,  and  about  twice  the  diameter  of 
the  stems,  with  the  ovate-acute  sporophylls  in  four  ranks. 
The  megaspores  are  of  a  pale  lemon  colour,  and  the  mi- 
crospores dark  orange.  According  to  Mr.  Eaton,  who 
described  this  species,  the  megaspores  and  microspores 
are  developed  in  separate  spikes. 

Selaginella  cinerasccns  is  found  on  dry,  bare  hills  in 
southern  California.  For  a  time  after  it  was  described, 
it  was  confused  with  another  species  called  Selaginclla 
hryoidcs,  described  by  Nuttall,  and  some  of  the  earlier 
references  to  it  will  be  found  under  the  latter  name. 

T'he  Oregon    Selaginella. 

One  of  the  most  remarkable  of  the  selaginellas  is  the 
Oregon  selaginella  {^Selaginella  Oregana)  which,  until   it 


Selnginella  Or  eg  ana. 


THE  SiLAGlNcLLA  RUPESTRIS  GROJ?.  149 

was  recently  discovered  in  northwestern  Washington  by 
Mr.  J.  B.  P^lett,  was  supposed  to  grow  in  Oregon  only. 

Although  its  stems  are  less  than  a  sixteenth  of  an  inch 
in  diameter,  they  are  said  occasionally  to  reach  a  length  of 
six  feet.  As  a  consequence  it  is  a  pendent  species, 
growing  with  mosses  on  the  trunks  of  trees  and  emitting 
copious  roots,  from  both  stem  and  branches,  that  strike 
into  the  bark  and  hold  the  plant  in  place. 

The  stems  are  pinnately  branched  like  those  of  Selagi- 
nella  Bigclovii,  though  the  lateral  branches  are  longer 
and  farther  apart,  with  fewer  branchlets.  The  stems  are 
light  brown  in  colour,  and  so  sparingly  covered  w^ith 
leaves  as  to  be  noticeable,  especially  in  the  older  parts  of 
the  plant.  The  leaves  are  narrow,  about  a  twelfth  of  an 
inch  long,  with  a  short  white  awn  at  apex  and  occasional 
cilia  on  the  margin.  Those  on  the  branchlets  are  dark 
green  and  loosely  spreading;  on  old  branches  they  are 
light  brown  and  half  appressed.  Some  of  the  leaves 
early  lose  their  terminal  awns,  and,  in  consequence,  in 
some  books  this  species  has  been  described  as  awnless. 
The  fruiting-spikes  are  slender,  four-angled,  and  appar- 
ently not  very  abundant. 

This  species  is  found  in  the  dense  forests  near  the 
Pacific  coast  and  grows  in  tangled  mats.  Mr.  Thomas 
Howell,  author  of  a  "  Flora  of  Northwest  America," 
writes  that  he  found  it  growing  from  the  branches  and 
prostrate  trunks  of  maple  trees,  from  which  it  hung  to  a 
length  of  from  six  inches  to  three  feet.  It  often  grows 
among  mosses,  one  of  which,  Hypnnvi  lorciivi,  might  be 
mistaken  for  it  at  first  glance.  Mr.  Howell  is  of  the 
opinion  that  its  season  of  growth  is  from  September  to 
June.  The  plant  has  always  been  spoken  of  as  Selagi- 
nclla   Oregana  and   will  be  found  in   most  books  under 


t5o  THE  SELAGINELLA  RUPESTRIS  GROUP. 


that  name,  but  it  was  earlier  given  the  name  of  Sclagi- 
nella  strutJiioloidcs  and  tliis  is  one  of  the  names  by  which 
it  is  likely  often  to  be  called  in  future.  ^ 

The  Prickly  Mountain  Moss. 

If  the  fern  allies  were  placed  in  genera  founded  upon 
external  appearances  alone,  that  plant  which  the  British 
call  the  prickly  mountain  moss  [Sclaginella  spinosii) 
would  be  found  among  the  lycopodiums.  It  has  a 
very  decided  resemblance  to  the  marsh  club-moss  and  is 
about  the  same  size,  but  the  fact  that  the  fertile  spikes 
bear  both  microsporangia  and  megasporangia  for  ever 
separates  it  from  the  true  club-mosses. 

Like  the  bog  club-moss,  and  unlike  most  of  the 
selaginellas,  there  is  a  marked  difTerence  between  the 
fertile  and  sterile  stems.  The  latter  are  close  to 
the  ground,  very  slender  and  threadlike,  with  occasional 
short  branches  half  an  inch  or  more  long.  The  entire 
sterile  portion  seldom  reaches  a  length  of  more  than 
four  inches  and  bears  roots  only  near  the  base.  The 
leaves  are  loosely  spreading  and  arranged  on  all  sides  of 
the  stem.  They  are  broadly  lanceolate,  acute,  and  the 
margins  are  beset  with  scattered  teeth  too  stout  to  be 
called  cilia. 

The  fertile  spikes  grow  from  near  the  base  of  the  main 
sterile  stems  and  reach  a  height  of  three  inches  or  more. 
They  are  quite  erect  and  resemble  the  fruiting-stems  of 
a  Lycopodium  since  they  consist  of  a  leafy  stal-k  sur- 
mounted by  a  loose  cone  of  sporophylls.  The  leaves  on 
the  stalk  are  similar  to  those  on  the  sterile  stem,  though 
slightly  larger  and  more  closely  appressed.  As  they 
merge    into    the  sporophylls    they    become    larger    and 


PRICKLY  MOUNTAIN   MOSS.     Selaginella  sphiosa. 
(Slightly  enlarged.) 


THE  SELAGINELLA  RUPESTRIS  GROUP.  151 

broader,  with  stronger  teeth,  and  often  stand  at  nearly 
right  angles  to  the  stem,  making  the  cone  quite  conspic- 
uous. The  cones  are  an  inch  or  more  long,  and  usually 
there  is  but  one  fertile  spike  on  each  plant.  The  lowest 
sporophylls  bear  three  or  four  megaspores,  which  are  as 
large  as  the  seeds  of  many  flowering-plants.  The  fertile 
spike  is  deciduous,  but  the  sterile  stems  survive  the 
winter. 

Selaginella  spinosa  is  rare  in  the  United  States,  being 
found  only  in  the  elevated  parts  of  Maiu'e,  New  Hamp- 
shire, New  York,  Michigan,  and  Colorado.  In  British 
America  it  is  more  abundant  and  found  at  lower  alti- 
tudes. It  is  also  found  in  both  Alaska  and  Greenland. 
In  the  Old  World  it  is  reported  from  the  British  Isles 
and  across  the  northern  part  of  the  Continent,  extending 
south  to  Germany.  It  delights  in  moist,  grassy  places, 
being  much  like  the  club-mosses  in  this  respect.  The 
name  of  prickly  mountain  moss  is  in  allusion  to  the 
toothed  leaves,  though  these  are  in  no  wise  either  spiny 
or  prickly.  The  specific  name  also  alludes  to  this  cir- 
cumstance. In  the  days  when  this  was  thought  to  be  a 
club-moss  it  was  called  Lycopodiiun  selaginelloides,  or  the 
selaginella-like  club-moss.  Its  transference  to  the  genus 
Selaginella  has  made  this  specific  name  meaningless. 


THE  CREEPING  SELAGINELLA 
GROUP. 


THE   CREEPING   SELAGINELLA 
GROUP. 


HE  genus  Sclaginella  contains  by  far 
the  greater  number  of  the  fern  allies, 
and  the  sub-genus  StacJiygyjiandruni, 
to  which  our  creeping  species  belong, 
comprises  nearly  three  fourths  of  the 
species  in  the  genus.  The  sub-genus, 
however,  was  not  founded  upon  the 
creeping  habit,  for  many  of  the  spe- 
cies have  erect  or  ascending  stems, 
but  all  agree  in  having  two  sorts  of  leaves  like  our  creep- 
ing species,  thus  sharply  distinguishing  them  from  the 
relatives  of  Sclaginella  rupcstris.  Notwithstanding  the 
great  number  of  species  in  this  section  it  is  very  poorly 
represented  in  North  America.  It  is  a  characteristically 
tropical  group,  and  our  species  seem  in  the  nature  of  un- 
usual extensions  northward. 


'The  Creeping  Selaginella. 

The  creeping  sclaginella  par  excellence,  and  the  least 
conspicuous,  is  the  one  known  to  botanists  as  Sclaginella 
apus.  What  the  curly  grass  or  the  little  grape  fern  is  to 
our  other  ferns,  this  species  is  to  its  relatives  among  the 


156  THE  CREEPING  SELAGINELLA  GROUP. 

fern  allies.  Owing  to  its  small  size,  creeping  habits, 
and  general  resemblance  to  the  mosses  and  hepatics,  it  is 
very  difficult  to  find  for  the  first  time;  but  when  once 
its  characteristic  haunts  are  known,  the  collector  finds  it 
again  with  ease. 

The  stems  are  from  two  to  four,  inches  long  and  lie 
close  to  the  earth,  to  which  they  are  attaclied  by  numer- 
ous slender  forking  roots  emitted   from  all  parts  of  the 


CREEPING  SELAGINELLA.     Selaginella  A/>us. 

plant.  From  the  main  stems,  scattered,  alternate,  pros- 
trate branches  are  given  off,  the  longest  reaching  a 
length  of  two  inches  or  more  and  again  branching.  The 
leaves  are  borne  on  all  parts  of  the  stem  and  branches, 
and  are  remarkable  not  only  for  being  of  two  sizes,  but 
for  being  borne  in  two  different  planes.  The  larger 
leaves  are  scarcely  an  eighth  of  an  inch  long,  ovate, 
acutish  or  obtuse,  unequal-sided,  with  the  broadest  side 
toward  the  tip  of  the  stem.  They  are  very  thin,  witli 
serrulate  margins  and  distinct  mid-ribs,  and  are  arranged 
alternately    on    the    stem,    from    which    they    spread    at 


THE  CREEPING  SELAGINELLA  GROUP. 


right  angles.  Alternating  with  these  larger  leaves  is  a 
series  of  smaller  ones  attached  to  the  stem  on  the 
upper  side,  to  which  they  are  closely  appressed,  with 
their  tips  pointing  outward.  These  smaller  leaves  are 
about  half  the  size  of  the  others,  and,  like  them,  are 
somewhat  unequal-sided.  They  are  ovate  at  base  and 
end  in  a  tapering  point. 

The  fruit-spikes  are  half  erect  and  are  borne  on  the 
ends  of  the  branches,  from  which  they  differ  little  in 
appearance  except  in  being  more  leafy.  They  are  ob- 
scurely four-angled, and  the  lens  shows 
them  to  consist  of  four  rows  of  sporo- 
phylls  of  equal  size.  This  is  explained 
upon  the  supposition  that  in  the 
fruiting-spikes  the  two  rows  of  small 
leaves  on  the  stems  have  become  as 
large  as  the  others.  The  spikes  are 
under  half  an  inch  long  and  are  usually 
borne  singly.  The  sporophylls  are 
ovate,  sharp-pointed,  and  keeled  in  the 
upper  half. 

The  majority  of  our  selaginellas  are  found  in  dry  situ- 
ations, but  the  present  species  is  a  lover  of  moisture  and 
is  found  in  wet  meadows  and  pastures  in  company  with 
mosses  and  sedges.  It  is  frequently  abundant  on  the 
bare  soil  at  the  base  of  sedge  tussocks  and  on  the  sides 
of  channels  formed  by  tiny  rills.  It  must  often  be 
sought  on  hands  and  knees,  though  it  is  occasionally  so 
plentiful  as  to  form  close  mats.  In  the  vicinity  of  New- 
York  it  is  frequently  found  on  damp  lawns.  It  is  ex- 
ceedingly like  some  of  the  mosses  of  the  genus  Milium, 
but  can  always  be  distinguished  from  them  by  its  leaves 
of  two  sizes.     Its  colour  is  of  a  characteristic  and  deli- 


Spike.     (Enlarged.) 


158  THE  CREEPING  SELAGINELLA  GROUP. 

cate  yellowish  green,  and  in  time  becomes  so  well  known 
as  to  be  singled  out  by  the  eye  at  considerable  distances. 

Most  authorities  consider  this  plant  an  annual,  but 
this  is  clearly  a  mistake.  It  may  be  found  as  soon 
as  the  snow  disappears,  though  the  spores  are  not 
ripe  until  August  or  September.  The  beginner  has  the 
best  chance  of  finding  it  early  in  spring,  before  the  grass 
has  begun  to  green.  It  is  then  most  easily  found  in  wet 
pastures  and  in  grass  fields  damp  enough  to  permit  of  a 
growth  of  mosses.  The  hue  of  its  fronds  makes  it  then 
very  conspicuous. 

The  creeping  selaginella  is  found  from  Maine  and 
Ontario  to  Florida,  Texas,  and  British  Columbia.  In 
the  greater  part  of  its  range  it  does  not  seem  to  be 
abundant,  but  its  small  size  and  resemblance  to  the 
mosses  may  often  enable  it  to  live  undiscovered. 

Selaginella    L,udoviciana. 

In  the  American  tropics  there  are  at  least  half  a  dozen 
species  of  Selaginella  so  nearly  like  the  creeping  sela- 
ginella that  they  might  easily  be  mistaken  for  it,  and  the 
species  called  Selaginella  Lndoviciana  is  one  of  this  num- 
ber. Indeed  it  has  often  been  suggested  that  Selaginella 
Lndoviciana  may  be  only  an  erect  variety  of  the  com- 
mon creeping  species,  the  differences  it  presents  being 
accounted  for  by  the  different  climate  in  which  it  grows. 
To  one  who  has  seen  it  in  its  native  haunts,  however,  it 
does  not  appear  to  possess  many  of  the  characteristics 
oi  Selaginella  apus,  except  that  in  the  shape  and  size  of 
the  leaves  the  two  are  nearly  alike.  The  stems  are  from 
six  to  eight  inches  in  length  and  strong  enough  to  hold 
themselves    nearly  erect,  and    the    roots  usually  appear 


Selaginella  L iKhwiciana, 


THE  CREEPING  SELAGINELLA  GROUP.  159 

from  only  the  lowest  joints  of  the  stem.  The  stem  is 
bianclied  as  in  Selaginella  apiis,  but  the  longer  basal 
branches  are  nearly  upriglit,  though  their  branchlets, 
especially  during  the  growing  season,  droop  gracefully 
away  from  the  main  axis  of  the  plant. 

This  species  begins  growth  early  in  the  year,  and  by 
the  middle  of  April  the  stems  are  mature.  The  sporan- 
gia are  borne  in  the  axils  of  the  leaves  at  the  tip  of  the 
branchlets,  and  the  fruiting  parts  have  more  of  a  resem- 
blance to  a  cone  than  they  have  in  Sciagiiiella  apus, 
owing  to  the  fact  that  the  sporophylls  are  less  spreading. 
The  spikes  of  fruit  are  often  more  than  half  an  inch 
long  and  are  usually  abundant.  The  spores  are  ripe  in 
May  or  earlier. 

Although  both  kinds  of  leaves  are  like  those  of  Sela- 
ginella  apiis,  it  may  be  noted  that  they  are  slightly 
longer  for  their  width  and  somewhat  thicker  than  in  that 
species.  The  sporophylls  also  have  longer  tips.  These 
differences,  however,  are  not  apparent  until  viewed  with 
a  lens. 

Selaginella  Lndovieiaua  has  thus  far  been  found  only 
in  a  few  scattered  localities  in  Florida,  Alabama,  and 
Louisiana.  It  was  first  discovered  by  Drummond  at 
Covington,  in  the  latter  State.  The  author  has  collected 
it  at  Pearl  River,  and  it  has  been  found  in  several  other 
places  in  the  vicinity  of  New  Orleans.  Its  favourite 
haunts  are  the  more  open  spots  in  the  sandy  pine  barrens. 
It  does  not  appear  to  be  quite  so  dependent  upon  mois- 
ture as  the  creeping  selaginella  but  it  is  by  no  means  a 
dry-ground  species.  It  is  probably  not  uncommon  in 
suitable  situations  along  the  Gulf  coast  and  may  yet  be 
found  in  Texas.  The  illustration  is  made  from  plants 
collected  by  Prof.  R.  S.  Cocks  at  Mandeville,  Louisiana. 


i6o  THE  CREEPING  SELAGINELLA  GROUP. 

Selaginella    Douglasii. 

The  species  named  Selaginella  Douglasii  is  one  of  the 
rarest  of  the  fern  allies  in  collections.  It  is  reported  to 
grow  in  northern  California,  Oregon,  Washington,  and 
British  Columbia,  but  it  appears  to  be  seldom  found. 
It  is  more  rigid  than  Selaginella  apns,  but  has  much  the 
same  appearance,  spreading  over  the  ground  and  rooting 
from  various  parts  of  the  stem. 

This  is  a  somewhat  larger  plant  than  the  creeping 
selaginella,  often  reaching  a  foot  in  length.  It  is  regu- 
larly and  alternately  branched,  and  these  branches  are 


Selaginella  Douglasii, 
branched  once  or  twice  more  in  the  same  manner.  The 
leaves  are  similar  in  size  to  those  of  Selaginella  apns,  but 
firmer  in  texture.  The  lateral  rows  are  very  blunt,  but 
the  small  leaves,  though  blunt,  are  tipped  with  a  short 
whitish  point.  The  leaves  are  thickly  crowded  on  the 
branches    and    branchlets,    the    lateral    ones,    as    usual, 


PLATE  VII.     SELAGINELLA   LUDOVICIANA. 


CCPyRlOHT,    1906,    BY    FREIERICK    A.    STCKES   COMPA^ 


THE  CREEPING  SELAGINELLA  GROUP.  i6i 

spreading  at  nearly  right  angles  to  the  stem,  and  the 
upper  leaves  nearly  parallel  to  it.  Both  kinds  are  occa- 
sionally ciliate  at  base.  The  spores  are  borne  in  distinct 
four-sided  cones,  about  half  an  inch  long,  on  the  tips  of 
the  branches.  The  tips  of  the  sporophylls  are  blunt, 
and  until  maturity  are  closely  appressed  to  the  stem. 
The  cone  alone  is  nearly  sufficient  to  distinguish  the 
species.  Our  illustration  was  made  from  specimens  col- 
lected in  northern  Oregon,  kindly  sent  by  Mr.  J.  B. 
Flett. 

The   Resurrection    Moss. 

There  are  two  principal  ways  by  which  the  scanty 
vegetation  of  the  more  arid  parts  of  the  earth  manages 
to  exist  in  spite  of  the  lack  of  moisture.  In  plants  like 
the  cactus,  with  a  thick  epidermis,  the  moisture  accumu- 
lated during  the  occasional  rains  is  carefully  hoarded  and 
very  slowly  given  back  to  the  air.  In  other  plants,  lack- 
ing this  thick  epidermis,  it  has  been  found  possible  to 
dry  up  in  the  intervals  between  rains  and  revive  again  at 
the  first  return  of  moisture.  Many  ferns  and  various 
flowering-plants  have  this  faculty,  but  none  are  better 
known  because  of  it  than  the  little  plant  called  the 
resurrection  moss  {^Selaginella  IcpidopJiylld).  This  is 
due  in  large  measure  to  the  itinerant  venders,  who,  in 
their  efforts  to  sell  specimens  of  it,  have  told  many  won- 
derful stories  about  it.  It  is  commonly  asserted  that  it 
needs  only  to  be  placed  in  water  for  a  day  to  develop  a 
handsome  spike  of  flowers.  The  truth  of  the  matter  is 
that,  when  dried,  the  plant  curls  up,  forming  a  compact 
brown  ball  which  may  be  preserved  in  that  condition  for 
months,  and  then,  upon  being  placed  in  water,  will  uncoil 


1 6: 


THE  CREEPING  SELAGINELLA  GROUP. 


and  become  fresh  and  green  again  in  a  few  hours, —  a 
fact  in  itself  ahiiost  as  marvellous  as  the  stories  told  of  it. 
The  plants  may  be  thus  alternately  dried  and  relaxed 
many  times,  but  it  should  not  be  supposed  that  such 
plants  are  alive  and  will  grow.  The  spreading  of  the 
fronds  is  simply  due  to  the  way  in  which  the  tissues 
absorb  water.  When  rooted  in  the  soil  of  their  native 
home,  however,  they  do  not  die  during  drouth,  and  when 
they  relax  again  in  the  rainy  season  new  growth  really 
takes  place. 

Selaginella  lepidophylla  is  a  native  of  our  arid  South- 
west, and  there  grows  on  the  tops  of  the  sunbaked  rocks 
in  regions  where  rain  does  not  fall  for  a  year  or  more  at 
a  time.  During  such  periods  its  fronds  remain  com- 
pactly folded,  their  colours  blending  with  the  dry  earth. 
When  rain  comes  they  at  once  awake  and  spread  out  in 
bright  green  rosettes,  appearing  as  luxuriant  as  if  drouths 
were  unknown.  Notwithstanding 
the  trying  conditions  to  which 
they  are  subjected,  they  often 
cover  considerable  areas  as  thickly 
as  dandelions  on  a  lawn. 

The  branches,  flattened  dorsi- 
vent rally,  rise  from  a  central  crown 
and  produce  roots  only  near  the 
base.  They  are  very  numerous, 
from  two  to  four  inches  long,  with 
branchlets  that  fork  at  the  ex- 
tremities in  such  a  manner  as  to 
be  nearly  fan-shaped.  The  leaves 
are  arranged  in  four  rows  as  usual,  those  on  the  sides  of 
the  stem  being  an  eighth  of  an  inch  or  less  in  length,  thick, 
oblong,  minutely  ciliate,  and  very  obtuse ;  those  on  the 


Branch  of  Resurrection  Moss. 


>C  X'^x. 


::^f^^Wfl^ 


RESURRECTION  MOSS.     Selaginella  LcpidopJiylla, 


THE  CREEPING  SELAGINELLA  GROUP.  163 

upper  surface  are  nearly  as  long  and  scarcely  differ  in 
shape.  The  lateral  leaves  are  ascending,  but  the  upper 
rows  are  nearly  parallel  with  the  branchlets  that  bear 
them.  Both  kinds  are  closely  imbricated,  and  are  likely 
to  be  faintly  white-margined.  The  fruiting-spikes  are 
borne  on  the  end  of  the  branchlets.  They  are  square, 
half  an  inch  or  less  long,  with  triangular  sporophylls 
strongly  keeled  on  the  back.  In  old  plants  the  leaves 
turn  a  reddish-brown  on  the  under  surface. 

In  recent  years  a  considerable  trade  in  this  plant  has 
sprung  up,  the  large  dealers  ordering  in  lots  of  ten 
thousand  or  more.  They  are  sold  mostly  to  collectors 
of  curios.  Mr.  J.  H.  Ferriss  tells  me  that  in  the  yards 
of  settlers  at  the  mouth  of  the  Pecos  River  in  Texas  he 
has  seen  waggon-loads  of  this  plant  drying,  preparatory 
to  being  shipped  to  Eastern  dealers. 

Selaginella  IcpidopJiylla  is  found  in  Arizona,  New 
Mexico,  and  Texas  in  suitable  situations.  Though  not 
widely  distributed  within  our  limits  it  is  a  very  common 
species,  and  its  range  extends  southward  across  the 
tropics  to  Peru.  It  is  often  called  "  bird's-nest  moss," 
in  allusion  to  the  way  the  fronds  roll  up  when  dry.  It 
is,  however,  most  widely  known  as  the  resurrection 
plant. 

Selaginella    Pringlei. 

This  species,  named  for  the  veteran  collector,  C.  G. 
Pringle,  resembles  Selaginella  lepidopJiylla  very  much, 
spreading  out  in  similar  green  rosettes  in  moist  weather 
and  rolling  up  when  dry.  The  leaves  are  of  the  same 
size,  but  more  pointed,  and  are  further  distinguished  by 
being  tipped  with  a  hard,  whitish,  awn-like  point  nearly 


i64  THE  CREEPING  SELAGINELLA  GROUP. 

as  long  as  the  body  of  the  ieaf.     The  fruiting-spikes  are 
short,  with  less  triangular  sporophylls. 

The  plant  has  been  collected  in  Mexico  and  was 
found  in  the  Chenate  Mountains  of  Texas  by  Neally. 
Owing  to  its  being  easily  confusecl  with  Sclaginclla 
lepidophylla,  but  little  is  known  about  it,  and  even  its 
range  cannot  be  properly  defined.  More  notes  concern- 
ing it  are  very  much  needed.  Both  this  species  and  the 
preceding,  when  growing,  have  a  strong  resemblance  to 
the  exotic  selaginellas  commonly  cultivated,  and,  owing 
to  their  manner  of  growth  in  circular  tufts,  are  desirable 
additions  to  the  conservatory  for  their  contrast  to  the 
other  species. 

Selaginella    Pilifera. 

According  to  Baker's  "Fern  AW'xqs,''  Selaginella  pili- 
fera has  been  collected  in  Texas  by  Wright,  but  no 
recent  collector  has  found  it,  and  the  opinion  is  held  by 
most  American  students  that  the  plant  does  not  now 
occur  within  our  limits.  Its  habitat  is  the  plateau  of 
central  Mexico,  and  it  may  possibly  stray  northward  in 
the  Southwest.  The  following  description  should  aid 
collectors  in  identifying  it  should  they  find  it.  The 
lateral  leaves  are  ovate,  oblique,  very  small,  pale  green, 
rigid,  and  tipped  with  a  short  point.  They  are  serrulate, 
with  the  upper  side  of  the  base  dilated  and  ciliated. 
The  upper  leaves  are  half  as  long  as  the  others,  lanceo- 
late, and  also  cuspidate.  The  spikes  are  square,  less 
than  half  an  inch  long,  with  ovate-lanceolate  strongly 
keeled  sporophylls.  From  the  foregoing  it  will  be  seen 
that  it  is  a  plant  much  like  Selaginella  Pringlei,  and  col- 


RESURRECTION   MOSS.     Selagindla  Lepidophylla. 
When  dry. 


THE  CREEPING  SELAGINELLA  GROUP.  165 

lectors  who  find    the   latter  plant  should  look  carefully 
for  this  one. 


In  1904  Mr.  C.  F.  Saunders  discovered  in  southern 
California  an  apparently  undescribed  selaginella,  of  the 
Selaginella  rupestr is  group,  which  has  not  yet  been  named. 
In  the  same  year  Mr.  A.  A.  Eaton  brought  back  from  a 
trip  to  southern  Florida  specimens  which  have  since  been 
referred  to  the  tropical  Selaginella  Caribensis  a  near  ally 
of  the  creeping  selaginella.  This  plant  is  not  uncom- 
mon in  the  West  Indies,  but  is  likely  never  to  be  more 
than  a  rare  or  adventive  plant  in  our  territory.  It  is 
a  stronger  and  heavier  plant  than  the  creeping  sela- 
ginella and  will  be  recognized  at  once  from  its  resem- 
blance  to  that   species. 


THE  SALVINIACE/E, 


THE  SALVINIACE/E, 


•INCE  all  vegetation  requires  a  cer- 
tain amount  of  water  for  its 
processes,  it  is  not  unusual  for 
various  species  of  plants  to  be 
found  growing  in  swamps  and 
bogs,  or  even  in  lakes  and  ponds, 
but  cases  in  which  plants  have 
entirely  severed  their  connection 
with  the  earth  and  taken  to 
floating  on  the  surface  of  the 
water  are  far  less  common.  In 
a  survey  of  the  vegetable  kingdom,  however,  we  find 
that  all  the  great  groups  have  species  or  even  whole 
families  that  have  adopted  this  mode  of  life.  Among 
the  flowering-plants  the  little  duckmeats  {Lcinna)  are 
likely  first  to  come  to  mind,  but  there  is  the  great  water 
hyacinth  {Piaropus),  of  Southern  waters,  and  many 
another,  like  the  bladdervvorts,  nearer  home.  Among 
the  liverworts  various  species  of  Riccia  are  found  float- 
ing, and  even  the  ferns  have  provided  an  instance  in  that 
remarkable  floating  fern,  Ccratopteris  tJialictroides.  It  is 
not  surprising,  then,  to  find  a  family  of  the  fern  allies 
like  the  Salviniace^  committed  to  such  an  existence. 
Indeed  it   is  sometimes  suggested  that  the  Salviniaceae 


ijo  THE  SALVINIACE/E. 

have  arisen  through  some  sucli  ancestor  as  the  floating 
fern,  though  as  a  matter  of  present  relationships  the 
species  of  this  group  appear  to  have  closer  affinities  for 
the  filmy  ferns  (Hymcnoplu'llace.x),  especially  as  regards 
the  formation  of  their  sporocarps.  In  any  event  they  arc 
probably  more  closely  allied  to  the  ferns  than  any  of  the 
other  fern  allies  except  the  Marsiliacea^,  and  some  are 
so  much  like  ferns  in  their  structure  as  to  have  received 
the  common  name  of  water-fern.  As  a  class  they  are, 
with  the  Marsiliace^e,  sometimes  spoken  of  as  the 
Hydropterids  (which  may  be  translated  as  water-ferns), 
or  as  Rhizocarps,  which  refers  to  the  way  the  sporocarps 
are  borne  in  these  families. 

The  Salviniaceae  contain  but  two  small  genera,  Sa/- 
vinia  and  Azolla,  and  these  differ  markedly  in  structure. 
All  of  them,  owing  to  their  position  on  the  water,  are 
dorsi-ventral,  the  stem  growing  horizontally.  In  Azolla, 
roots  are  sent  down  into  the  water,  and  at  first  glance 
this  seems  to  be  the  case  in  Salvinia  also,  but  a  closer 
inspection  shows  that  what  appear  to  be  roots  in  this 
genus  are  really  dissected  leaves  and  that  the  species  are 
rootless.  Above  the  water  the  vegetative  leaves  spread 
out,  those  of  Salvinia  oblong  and  entire,  while  those  of 
Azolla  are  cut  into  more  fern-like  shapes.  In  most 
species  numerous  lateral  branches  are  given  off  by  the 
main  stem,  and  these  readily  separate  from  the  plant 
when  the  water  is  agitated,  and  form  new  plants.  A 
rough  day  on  the  water,  therefore,  greatly  assists  in 
multiplying  their  numbers. 

The  spores  are  of  two  kinds,  as  in  Selaginella  and 
Isoetes,  and  are  borne  in  structures  called  sporocarps,  or 
conceptacles  which  appear  to  be  special  forms  of  an 
indusium.     They  are  much  like  what  would  result  if  the 


THE  SALVINIACE/E. 


171 


urn-like  indusia  of  tlie  filmy  ferns  should  completely 
enclose  the  sporangia.  In  Salvinia  the  sporocarps  are 
borne  on  the  submerged  leaves,  usually  in  clusters  of 
three  ;  in  Azolla  they  are  borne  in  pairs  in  the  axils  of 
the  aerial  leaves.  Some  of  the  sporocarps  in  each  cluster 
of  Salvinia  always  bear  megasporangia.  There  are  about 
ten  in  each  sporocarp,  and  each  megasporangium  bears  a 
single  large  ovoid  megaspore.  The 
microsporangia  are  more  numerous, 
globose,  and  contain  a  large  number 
of  microspores.  In  Azolla  the  pairs 
of  sporocarps  are  usually  of  two 
sizes,  the  smaller  bearing  a  single 
megaspore,  and  the  larger  producing  several  microspo- 
rangia and  numerous  microspores.  The  mature  sporo- 
carps drop  from  the  plant  and  promptly  sink  to  the 
bottom  of  the  water,  where  they  continue  to  enclose  the 
spores  for  some  time.  The  latter  are  finally  liberated  by 
the  decay  of  the  walls  surrounding  them.  The  micro- 
spores of  y4-S6'/Z^  are  usually  held  together  by 
a  solid  sort  of  protoplasm  which  produces 
hooked  processes  from  the  outer  surface. 
The  sporocarp  appears  to  be  an  outgrowth 


Cross-seclion  of  Salvinia 
sporocarps.  (Enlarg-ed.) 


Sporocarps  of 

Azolla. 

(Enlar^ad.) 


of  the  leaf  that,   becrinnine  with 


rounding  the  sporangia,  slowly  increases 
until  it  has  completely  enclosed  them.  Before  this  has 
happened,  however,  certain  alg<Te  take  up  their  abode  in 
the  sporocarps,  and  when  the  latter  mature  they  go  into 
a  resting  condition,  forming  little  colourless  spheres. 
These  spheres  are  seldom  absent  from  the  ripe  sporo- 
carps. 

The  genus  Salvinia  was  named   for  Salvini,  a  Floren- 
tine professor.     There  are  about  a  dozen  species  known 


172  THE  SALVINlACE>e. 

to  science,  most  of  them  in  tropical  waters.  The  name 
Azolla  is  derived^  from  two  Greek  words  meaning  "  to 
dry "  and  "  to  destroy,"  and  is  most  appropriately 
applied  to  these  delicate  little  plants  whose  life  is  so 
closely  dependent  upon  moisture.  There  are  less  than 
half  a  dozen  species  in  the  world.  Like  the  salvinias 
they  delight  in  the  warm  waters  of  tropical  regions.  The 
species  in  both  genera  are  very  small,  the  largest  having 
leaves  not  more  than  two  inches  long,  while  in  a  majority 
they  do  not  reach  a  length  of  half  an  inch.  All  are 
supposed  to  be  short-lived,  possibly  annual  plants,  but  a 
few  seem  to  live  to  a  greater  age.  A  dozen  or  more 
species  of  Salvinia  have  been  found  in  a  fossil  state,  but 
usually  in  deposits  of  no  very  great  age. 


SALVINIA. 


SALVINIA. 

|t  may  be  seriously  doubted  whether  any 
species  of  Salvinia  is  native  to  North 
America.  In  all  books  devoted  to  the 
Pteridophytes  we  are  credited  with  one 
species,  Salvinia  natans,  but  the  evidence 
to  show  that  it  is  a  native  or  even  natural- 
ised is  far  from  convincing.  It  was  re- 
ported from  western  New  York  by  Pursh 
about  a  century  ago,  but  the  exact  locality 
has  always  remained  unknown,  if  it  ever 
really  existed.  The  only  other  record  is 
the  station  at  Oscher's  Lake  in  the  Bois 
Brule  bottoms  in  Perry  County,  Missouri,  where  it  was 
collected  by  C.  H.  Demetrio  in  November,  1886.  Mr. 
Demetrio  has  kindly  favoured  the  author  with  part  of 
the  original  collection  in  fine  fruit  and  with  an  account 
of  his  finding  it.  It  was  collected  but  once,  with  Azolla, 
while  on  a  fishing-trip  to  the  lake,  and  was  not  noticed 
among  the  other  specimens  until  they  were  being  pre- 
pared for  the  press  at  home.  It  has  apparently  never 
been  seen  since  at  this  station,  nor  has  it  ever  been 
collected  elsewhere  in  a  location  entirely  free  from  the 
suspicion  that  it  may  have  been  introduced,  and  it  seems 
but  fair  to  conclude  that  the  plant  is- not  native  to  North 
America. 

Paradoxical  as  it  may  seem,  this  plant,  so  rarely  found 


76 


SALVINIA. 


Salvitiia  nalans. 


in  this  country,  is  really  quite  abundant,  but  always  in 
cultivation.  Few  greenhouses  in  which  there  are  tanks 
of  water  plants  are  without  it,  and  it  has  become  domes- 
ticated, as  it  were,  in  many-small  ponds,  fountains,  and 

artificial  lakes. 
So  far  as  known 
it  has  show  n 
no  tendency  to 
spread  to  other 
waters  unless 
its  occurrence 
at  0*s  c  h  e  r  '  s 
Lake  is  an  in- 
stance. 
The  main  axis  of  Salvinia  natans  may  reach  a  length 
of  two  or  three  inches,  but  is  usually  shorter.  Along 
this  the  leaves  are  thickly  clustered  in  several  longi- 
tudinal rows.  Two  of  these  rows  on  the  under  side  of 
the  stem  are  finely  dissected  into 
thread-like  divisions,  and  go  down  in- 
to the  water  functioning  as  roots, 
since  there  are  no  true  roots ;  the 
others  float  on  the  surface.  These 
latter  are  half  an  inch  or  less  in 
length,  bright  green,  almost  as  broad 
as  long,  with  a  very  blunt  tip,  and 
slightly  heart-shaped  base.  Above 
they  are  thickly  set  with  very  short,  Sporocarps  of  SaWinia. 
soft,  branching  hairs  that,  though  apparently  so  insignifi- 
cant, are  of  great  importance  to  the  plant,  since  they 
keep  it  right  side  up  in  the  water.  It  is  practically  im*. 
possible  to  make  these  plants  float  with  the  upper  surface 
downward,  for  the  tiny  hairs  hold  great   numbers  of  air 


SALVINIA.  177 

globules  among  them,  which  push  the  plant  back  as  soon 
as  it  is  overturned.  Thus  the  plants  can  ride  secure  in 
the  heaviest  storms.  On  the  under  side  of  the  leaves 
there  are  also  numerous  fine  brown  pellucid  hairs.  The 
sporocarps  are  from  four  to  eight  in  a  cluster,  and  are 
borne  on  a  common  stalk  arising  from  the  submerged 
leaves. 

With  the  exception  of  the  two  questionable  stations 
in  the  United  States,  Salvinia  natans  is  found  only  in 
the  Old  World,  extending  from  the  south  of  France  to 
India  and  northern  China.  It  thrives  well  in  sunny 
pools,  spreading  rapidly  by  division  of  the  plant  body. 
It  is  also  easily  grown  in  a  dish  of  water  in  the  house. 
Crayfish  are  said  to  feed  upon  the  plant  when  other  food 
is  scarce. 


THE  AZOLLAS 


THE  AZOLLAS, 


c£^|i.  HE  azollas  are  the  members  of  the  Salvin- 
iaceae    oftenest    called    the  water    ferns, 


7^'^K       and  their  finely  divided  fern-like  fronds 

^^- '       well    merit    the  name.     Thous^h   few  in 

,^^..%,^        number  of    species,  and  small  and  deli- 

^"'^'  cate    as    individuals,    they  have  a  wide 

distribution  and  are  found  in  all  the  warmer  parts  of  the 

world.     In  North    Am.erica   we  have   two    species,    one 

Western  and  the  other  with  a  wider  range. 

A^olla    Caroliniana. 

If  asked  to  name  the  smallest  of  the  North  American 
fern  allies  one  need  have  no  hesitancy  in  mentioning 
Azolla  Caroliniana.  With  the  exception  of  its  Western 
congener  there  are  no  others  that  even  approach  its 
diminutive  proportions.  Three  or  four  full-grown  plants 
may  be  hidden  under  a  single  copper  cent,  and  yet  so 
abundant  is  this  species  that  vast  stretches  of  water  are 
often  completely  covered  by  it. 

Taken  singly,  the  plant  is  a  handsome  one.  Its  stems, 
so  slender  as  to  be  invisible  to  the  eye,  fork  several 
times,  and  are  covered  with  the  tiniest  of  two-lobed  over- 
lapping leaves,  from  pale  green  to  deep  red  in  colour. 


iS2  THE  AZOLLAS. 

As  they  float  on  the  surface  of  quiet  pools  their  resem- 
blance to  small  green  and  red  snowflakes  is  more  than 
an  idle  fancy.  From  the  stems  slender  rootlets  go 
down  into  the  water,  and  should  it  happen  that  the. plant 
is  stranded  by  reason  of  the  lessening  of  the  pools  in 
summer,  the  rootlets  ape  able  to  strike  into  the  mud 
and  so  continue  the  existence  of  the 
plant.  There  is  some  reason  for  be- 
lieving that  the  difTerences  in  the 
colour  of  the  fronds  are  due  to  differ- 
ences in  habitat,  those  growing  on  the 
water  in  full  sun  being  usually  tinged 
with  red,  while  those  that  root  in  the 
Azoiia  caroiiniana.  ^ud  are  nearly  always  deep  green. 
(Enlarged.)  This    spccics    is   supposcd  to  be  an 

annual,  but  the  author  has  found  it,  though  in  lessened 
numbers,  in  mid-winter  in  New  Orleans,  often  in  pools 
liable  to  have  a  thin  coating  of  ice.  It  develops  very 
rapidly  with  the  return  of  warm  weather,  and  by  mid- 
April  the  pools  back  of  the  levees  along  the  lower 
Mississippi  are  entirely  covered  by  it.  Some  idea  of  its 
possibilities  of  growth  may  be  gained  from  a  note  by 
Prof.  R.  S.  Cocks,  in  the  Fern  Bulletin  for  1904,  in 
which  he  says  that  in  Audubon  Park,  New  Orleans, 
between  the  months  of  June  and  September,  there  was 
removed  from  the  surface  of  a  pond  about  a  quarter  of 
an  acre  in  extent  no  less  than  fourteen  cartloads  of  this 
plant,  with  a  total  weight  of  seven  tons. 

The  sporocarps  are  borne  in  the  axils  of  the  leaves, 
and  in  addition  to  the  spore-cases  nearly  always  contain 
the  resting  bodies  of  a  certain  alga  {Anabcena  acollce.) 
As  soon  as  the  spores  begin  to  geriliinate,  these  resting 
bodies  of   the  alga   do    the    same,  and    as  soon  as  the 


J% 


SB- 


'■#^/- 


J 


THE  HOME  OF  AZOLLA. 


THE  AZOLLAS.  183 

Azolla  leaves  are  developed,  they  creep  into  the  hollow 
interior  through  a  pore  at  the  base  of  the  larger  lobe  of 
the  leaf,  and  there  form  colonies.  These  colonies  are 
nearly  always  found  in  Azolla  leaves. 

Azolla  Caroliniana  appears  to  grow  naturally  as  far 
north  as  New  York,  but  in  the  northern  part  of  its 
range  it  is  never  so  abundant  or  so  conspicuous  as  it  is 
nearer  the  equator.  It  is  found  throughout  the  South 
and  extends  to  Arizona  and  Washington.  It  occurs  in 
the  Mississippi  valley  at  least  as  far  north  as  Iowa,  but 
its  northern  range  is  not  well  defined.  Beyond  our 
limits  it  is  found  in  suitable  places  as  far  south  as 
northern  Patagonia.  It  delights  especially  in  still  waters 
and  is  seldom  found  in  streams.  It  is  easily  cultivated 
in  ponds  where  it  does  not  gr'ow  naturally,  and  has  been 
thus  naturalised  in  many  places,  one  of  the  best  known 
of  which  is  on  Staten  Island,  New  York. 

Azolla     Filiculoides. 

With  the  exception  that  Azolla  filiculoides  is  a 
slightly  larger  plant  than  Azolla  Caroliniana,  it  is  almost 
exactly  like  it  to  the  unaided  eye.  Study  with  the  lens, 
however,  shows  that  the  branching  in  the  present  species 
is  inclined  to  be  pinnate  in  form  and  the  fronds  elon- 
gated, while  in  Azolla  Caroliniana  they  are  more  deltoid 
in  outline.  The  large  lobe  of  the  leaves  in  Azolla  fili- 
culoides is  ovate,  while  that  of  the  other  is  rhombic- 
oblong  and  obtuse. 

Azolla  filiculoides  is  widely  distributed  in  South 
America,  being  most  abundant  on  the  Pacific  slope,  and, 
according  to  Baker,  is  found  in  the  Andes  up  to  an  ele- 
vation of   16,000  feet.     Within  our  limits   it  extends  to 


1 84 


THE  AZOLLAS. 


California  only,  but  is  often  abundant- there.  It  has  tlie 
same  habitat  as  our  common  species  and  appears  to 
thrive  in  cultivation.  Mr.  Eaton  states  that  he  has  seen 
ditches  in  California  covered  two  inches  deep  by  the 
multitudes  of  this  plant. 


Azolla  Filiciiloides, 
(Enlarged.) 


THE    MARSILIACE/E,    OR    PEPPER- 
WORTS. 


THE    MARSILIACE^. 


f^^N  account  of  the  way  in  which  the 
spores  originate,  the  Marsiliaceae 
and  Salviniaceye  are  believed  to  be 
closely  allied.  They  present  several 
differences,  however,  quite  as  strik- 
ing as  their  resemblances.  All  are 
lovers  of  the  water,  but  while  the 
species  of  Salviniacea^  are  floating,  those  of  the  Marsili- 
aceae are  rooted  in  the  mud  in  swampy  places  or  at  the 
bottom  of  ponds.  The  species  of  the  first  are  all 
regarded  as  annual,  while  those  of  the  latter  are  said  to 
be  perennial.  Both  bear  their  spores  in  sporocarps,  but 
these  are  very  different  structures  in  the  two  families. 
In  the  Salviniaceae  the  sporocarp  represents  a  single 
sorus  like  that  of  ordinary  ferns  ;  in  the  Marsiliaceae  the 
sporocarp  is  really  a  modified  leaf  and  contains  several 
sori.  It  may  be  likened  to  the  berry-like  structure  that 
encloses  the  sori  in  the  sensitive  fern  {Onoclea).  Like 
the  Salviniaceae,  this  family  also  consists  of  two  small 
genera,  Marsilia  and  Pihilaria,  both  most  abundant  in 
the  waters  of  the  warmer  parts  of  the  globe. 

Although  more  closely  related  to  the  ferns  than  any  of 
the  other  fern  allies,  the  Marsiliaceae  are  far  from  ferns 
in  appearance.     Nor  do  they  have  a  greater  resemblance 


i88 


THE  MARSILIACE^. 


Veiningin  leaf  of 
Marsilia. 


to  any  of  the  fern  allies.  The  leaves  of  the  marsilias 
are  always  four-parted,  with  slender  petioles  and  much 
resemble  those  of  oxalis  or  four-leaved  clovers.  Those 
of  Piliilaria  are  slender  tapering  organs,  in  outward  ap- 
pearance like  the  leafstalks  of  their  relatives.  In  both 
genera  the  leaves  rise  from  a  jointed  branching  rootstock 
growing  parallel  to  the  earth  and  sending  down  abun- 
dant rootlets  from  the  joints  or  occa- 
sionally from  other  parts  of  the  stem. 
The  leaves  are  coiled  in  the  bud,  like 
those  of  the  ferns,  and  in  Marsilia  they 
are  veined  like  them. 

The  sporocarps  are  from  one  to  six 
in  number  and  are  borne  on  short  pedi- 
cels that  spring  from  the  petiole  of  the 
leaf.  Usually  they  are  so  close  to  the 
stem  as  to  appear  to  be  borne  in  the  axils  of  the  leaves, 
though  in  one  exotic  species,  Marsilia  polycarpa,  they 
often  number  as  many  as  twenty,  and  are  strung  along 
the  petiole  for  some  distance,  each  on 
a  separate  pedicel.  In  Piliilaria  they 
are  usually  solitary.  In  Marsilia  the 
sporocarps  are  oblong,  and  in  Piliila- 
ria they  are  round.  From  their  shape 
and  size,  like  peppercorns,  the  mem- 
bers are  sometimes  called  pepperworts. 
The  Pilnlaria  sporocarp  contains  from 
two  to  four  chambers,  each  of  which 
contains  a  single  sorus  bearing  megasporangia  at  the  base 
and  microsporangia  at  the  tip.  The  megasporangia  each 
contain  but  a  single  megaspore,  while  the  microsporangia 
contain  numerous  microspores.  In  Marsilia  each  half 
of  the  sporocarp  may  be  considered  as  a  single  cell,  but 


Spo  roc  a  rp  of  ATars  ilia . 
(Enlarged.) 


mmm 


THE  MARSILIACE^.  189 

these  arc  separated  by  many  transverse  divisions,  each 
containing  a  sorus.  Around  the  inner  wall  of  the  sporo- 
carp  runs  a  gelatinous  ring  to  which  the  sori  are  attached, 
and,  when  the  sporocarp  opens,  this  ring  absorbs  water  and 
increases  enormously  in  size,  by  this  means  pushing  out 
of  the  sporocarp  and  drawing  the  sori  with  it.  The 
whole  process  may  be  completed  in  half  a  day,  and  may 
be  witnessed  by  any  who  will  take  the  trouble  to  soak  a 
Marsilia  sporocarp  in  waten  Before  soaking,  a  small 
part  of  the  outer  covering  of  the  sporo- 
carp should  be  chipped  off,  so  that  the 
water  may  enter.  The  small  oblong  sori, 
attached  to  the  almost  transparent  ring  ^^^M^^^ 
of  jelly,  make  it  a  most  interesting  object.  ff 

..,,  .  f     .  -iiir  1  1  Cross-section  of 

An  illustration  01   it  will  be  tound  at  the   PUuiaria  sporocarp. 

U        •         •  r     ,.1   •  1  4.  T7        1  (Enlarged.) 

beginning  01  this  chapter.  h.ach  sorus 
contains  both  megasporangia  and  microsporangia,  the 
former  few  in  number  and  each  containing  a  single  ivory- 
white  megaspore.  The  sporocarps  have  a  very  thick, 
hard  wall  almost  impervious  to  water,  and  may  remain 
beneath  the  water  for  a  long  time  without  opening.  So 
nearly  impervious  to  liquids  are  the  sporocarps  when 
uninjured,  that  they  have  been  kept  in  95^  alcohol  for 
nearly  six  years,  and  then  the  spores  still  had  vitality 
enough  to  germinate.  Sporocarps  dried  and  kept  in  the 
herbarium  for  eighteen  years  have  also  produced  spores 
capable  of  growing. 

The  sporocarps  of  Marsilia  finally  open  by  splitting 
into  halves.  Those  of  Pilnlaria  split  into  four  valves 
from  the  apex.  Since  the  sporocarps  are  modified  leaves, 
the  four  valves  of  the  .Pilnlaria  sporocarp  may  be  taken 
to  indicate  that  the  original  leaf  was  like  that  o{  Marsilia. 
Baker  therefore  states  that   the  leaf  in  Pilnlaria  is  now 


I90  THE  MARSILIACE^. 

merely  a  filiform  petiole.  The  prothallia  are  very  rudi- 
mentary and  develop  with  great  rapidity.  According  to 
Campbell  they  may  develop  from  the  spores  and  produce 
mature  sex-organs  in  twenty-four  hours. 

There  are  nearly  fifty  species  in  the  genus  Marsilia, 
mostly  in  tropical  regions.  Of  Piliilaria  there  are  about 
six  species,  widely  distributed.  Marsilia  was  named  for 
an  early  Italian  naturalist,  Aloysius  Marsili.  Pilularia  is 
from  the  Latin  word  for  a  '*  little  pill,"  and  is  in  allusion 
to  the  small  pilWike  sporocarps. 


Key  to  the  Marsilias. 


Sporocarps  usually  two  on  each  peduncle.  Eastern. 

M.  qiiadrifolia 

Sporocarps  rarely  more  than  one  on  a  peduncle 

Plant  nearly  smooth.     Southern  .  .     M.  uncinaia 

Plant  densely  hairy.     Western  .  .         M.  vestita 

Plant  larger,  less  hairy.     Southwestern  M.  inacropoda 


THE  MARSILIAS. 


THE  MARSILIAS. 


HERE  is  scarcely  a  genus  of  plants 
anywhere  whose  species  have  a 
more  general  resemblance  to  one 
another  than  the  genus  Marsilia. 
The  four-leaved  clover  is  the  un- 
varying pattern  after  which  the 
leaves  are  cut,  and  when  the  collector  has  once  seen  a 
single  species  he  will  have  no  trouble  in  referring  sub- 
sequent finds  to  its  proper  genus  at  least.  Specific 
differences  are  found  in  such  matters  as  size,  hairiness, 
and  the  number  and  arrangement  of  the  sporocarps. 
At  least  four  good  species  are  known  within  our  limits, 
only  one  being  found  in  the  Eastern  States,  the  others 
beincr  confined  to  the  West  and  Southwest. 


Marsilia   ^luadrifolia. 


Marsilia  quadrifolia  is  a  common  species  of  the  Old 
World  extending  from  southern  Europe  to  India,  China, 
and  Japan.  In  America  it  has  been  found  at  only  a 
single  station,  Bantam  Lake,  Connecticut,  and  this  cir- 
cumstance has  suggested  the  idea  that  it  is  not  really 
native  to  our  country.  But,  if  not  a  native,  the  plant 
has  become  so  thoroughly  settled  in  its  home  that  it 
may  justly  be  claimed    as  a  naturalised  member  of  our 


196  THE  MARSILIAS. 

flora.  From  the  original  station  plants  have  been  sent 
to  many  other  places,  and  in  each  they  have  grown 
luxuriantly,  vying  with  the  natives  in  their  ability  to 
hold  their  territory  and  to  gain  more.  The  pretty 
oxalis-like  leaves  resting  upon  the  water  or  rising  a  short 
distance  above  it  may  be  counted  as  an  addition  to  our 
lakes  and  ponds,  while  the  ease  with  which  it  may  be 
grown  makes  it  a  general  favourite.  It  may  even  be 
grown  in  a  tub  in  the  back  yard,  and  is  often  seen  in 
conservatories. 

In  its  native  haunts  Marsilia  qtiadrifolia  usually  roots 
in  the  mud  beneath  shallow  water,  the  very  slender 
rootstock,  a  yard  or  more  long,  creeping  above  the  soil 
and  sending  up.  great  numbers  of  leaves  on  slender 
petioles  that  elongate  until  they  reach  the  surface. 
While  this  is  the  usual  habitat,  it  may  often  be  found 
quite  out  of  water  at  midsummer.  The  leaves  are 
then  quite  short,  but  such  plants  are  usually  very  fruitful. 
The  joints  of  the  stem  are  short,  and  from  each  is  pro- 
duced a  tuft  of  roots  and  a  leaf.  In  the  bud  these 
leaves  are  coiled  and  the  four  divisions  folded  together, 
but  as  they  reach  the  air  they  unfold  and  spread  out  on 
the  water  like  the  leaves  of  the  water-lily.  In  vigorous 
specimens  the  petioles  often  hold  the  young  leaves 
above  the  water.  In  outline  the  blade  is  nearly  circu- 
lar, from  half  an  inch  to  two  inches  or  more  in  diam- 
eter, and  is  divided  into  four  equal  leaflets,  wedge-shaped 
at  base  and  rounded  on  the  outer  margins.  The  divisions 
are  marked  by  numerous  fine  veins  that  run  from  the 
petiole  to  the  margin,  forking  several  times.  The  young 
leaves  are  more  or  less  hairy,  but  when  full  grown  they 
are  smooth. 

The  .cporocarps  are  about  half  the  size  of  peas  and  are 


PLATE  VIII.     MARSILIA    QUADRIFOLIA. 


COPYRIGHT,    I9C5,    BV    FREDERICK    A.    STOKES   COMPANY 


THE  MARSILIAS.  i97 

borne  two  or  three  together  near  the  base  of  the 
leaves.  The  common  peduncle  is  about  half  an  inch 
long,  with  a  short  stalk  for  each  sporocarp  and  is 
usually  united  for  a  short  distance  with  the  petiole  of 
the  leaf.  In  colour  the  ripe  fruits  are  dark  purplish 
brown.  When  young  they  are  clothed  with  minute 
yellowish  hairs,  but  at  maturity  these  disappear.  The 
fruit  is  most  abundant  in  shallow  water.  At  the  point 
where  the  pedicel  appears,  to  join  the  sporocarp  there 
project  from  it  two  small  points  called  teeth.  In  this 
species  the  teeth  are  very  short  and  obtuse.  There  are 
from  sixteen  to  twenty  sori  in  each  sporocarp. 

Like  the  clover  and  oxalis,  which  it  resembles,  this 
species  has  the  habit  of  closing  its  leaves  at  night.  This 
is  done  by  two  of  the  leaves  rising,  folding  face  to  face, 
and  then  being  enfolded  by  the  other  two  in  the  same 
position  they  had  in  the  bud.  The  reason  for  this  so- 
called  sleep  position  is  doubtless  to  be  found  in  the  fact 
that,  like  most  water  plants,  the  stomata  or  openings 
for  transpiration  are  found  on  the  upper  surface,  and 
this  folding  is  in  some  way  concerned  with  their  protec- 
tion. It  is  noticeable  that  only  the  young  leaves  or 
those  rising  above  the  water  display  these  movements. 
When  taken  out  of  the  water  the  leaves  quickly  close  as 
in  the  night  position.  Baker  spells  the  specific  name 
quadrifoliata,  but  American  writers  do  not. 

Marsilia  Uncinata. 

Mar  si  Ha  uncinata  is  commonly  regarded  as  a  rare 
species,  and  in  the  latest  edition  of  Underwood's  text- 
book it  is  recorded  from  but  two  stations  in  the  United 


198  THE  MARSILIAS. 

States.  Ill  reality  it  is  an  abundant  plant  in  Louisiana, 
at  least,  being  common  for  more  than  two  hundred  miles 
along  the  Mississippi.  It  probably  occurs  in  moist 
grounds  throughout  the  State.  In  the  city  of  New 
Orleans  it  may  be  found  along  many  roadside  ditches, 
and  in  one  street  that  the  author  knows  of  it  grows  quite 
across  the  street. 

In  books  devoted  to  the  fern  allies,  all  the  dimensions 
of  the  marsilias  are  rarely  given.  The  length  of  the 
petiole  depends  almost  entirely  upon  the  depth  of  the 
water  in  which  the  plant  grows,  yet  measurements  of  it 
are  usually  included,  while  nothing  is  ordinarily  said  about 
the  length  of  the  rootstock.  In  the  present  species  the 
author  has  found  rootstocks  more  than  a  yard  long,  and 
longer  ones  are  probably  common.  Observations  on  this 
point  for  all  our  species  are  much  to  be  desired. 

In  the  size  and  shape  of  the  leaf  this  species  is  almost 
like  Marsilia  qiiadrifolia.  The  blade,  however,  is  likely 
to  be  sparsely  hairy,  even  at  maturity.  The  plant 
requires  a  wet  soil,  but  is  probably  as  common  out  of 
water  as  in  it.  It  is  often  found,  however,  rooted  in  the 
shallow  water  on  the  edges  of  the  bayous  and  sending 
long  floating  stems  into  deeper  water.  It  bears  fruit 
only  on  the  stunted  plants  in  drier  situations,  so  that 
fruited  herbarium  specimens  rarely  indicate  the  beauty 
of  this  plant  at  its  best. 

The  sporocarps  are  as  big  as  peas  and  are  borne  singly 
on  peduncles  half  an  inch  to  an  inch  or  more  long,  which 
appear  to  rise  from  the  axils  of  the  leaves.  They  are 
sparingly  clothed  with  pale -brown  hairs,  even  when 
ripe.  The  peduncle  terminates  in  two  rather  conspicu- 
ous teeth,  the  upper  of  which  is  usually  hooked,  from 
which  circumstance  the  plant  derives  its  specific  name. 


Mars  Ilia  Quadri folia. 


MiU'silia  Uncznata, 


THE  MARSILIAS.  199 

There  are  often  twenty-four  or  more  sori  in  each  sporo- 
carp.      A  specimen  is  illustrated  on  page  188. 

Marsilia  uncinata  is  now  known  to  occur  from  Louis- 
iana to  eastern  Texas,  and  it  is  probable  that  its  range 
will  be  still  farther  extended.  It  appears  to  be  plentiful 
in  the  delta  region  of  the  Mississippi.  When  first 
described  it  was  thought  to  be  a  variety  of  Marsilia  ves- 
tita,  but  its  longer  rootstock,  less  hairy  leaves,  and  spo- 
rocarps  will  distinguish  it  from  that  species.  In  its 
natural  habitat  Marsilia  uncinata  may  be  singled  out 
from  the  surrounding  vegetation  for  some  distance  by 
the  peculiar  fresh  green  colour  of  the  leaves.  During 
the  winter  months  either  the  plants  disappear,  or  the 
rootstocks  remain  in  a  resting  condition  without  leaves, 
though  they  reappear  early  in  the  new  year. 

Marsilia  Vest  it  a. 

The  smallest  of  our  marsilias,  and  the  one  with  the 
least  predilection  for  a  watery  habitat,  appears  to  be 
Marsilia  vestita.  While  it  often  grows  in  shallow 
water  it  is  usually  found  on  wet  muddy  banks,  where  it 
may  either  grow  in  dense  tufts  or  put  forth  short  exten- 
sions of  its  rootstock. 

The  petioles  are  from  one  to  five  inches  long,  and  the 
leaves  quite  small,  usually  under  an  inch  in  diameter. 
Both  leaf  and  petiole  are  clothed  with  soft,  short,  white 
hairs  that  may  be  either  spreading  or  appresseil.  These 
are  so  numerous  on  the  younger  parts  of  the  plants  as  to 
give  them  a  hoary  appearance.  The  outer  edge  of  the 
leaflets  is  rounded,  entire  or  occasionally  slightly  toothed. 
This  is  a  variable  plant,  however,  and  all  the  characters 
do  not  hold  for  single  specimens. 


200  THE  MARSILIAS. 

The  sporoCcirps  are  smaller  than  those  of  Marsi/ia 
unciiiata,  but  larger  than  those  of  MarsiUa  quadrifolia. 
They  probably  average  a  little  less  than  a  quarter  of  an 
inch  long.  They  are  borne  on  peduncles  so  short  as  to 
appear  sessile  or  nearly  so,  and  are  densely  covered  with 
the  fine  whitish  hairs  found  on  other  parts  of  the  plant. 
The  lower  tooth  of  the  sporocarp  is  short  and  blunt;  the 
other  is  slightly  longer  and  curved. 

Marsiliavestita\?>  found  from  Dakota  and  Washington 
to  Texas  and  California.  Southward  it  extends  into 
Mexico.  It  has  been  reported  as  naturalised  in  central 
Florida,  and  according  to  Baker  it  is  found  in  British 
Columbia  also.  Mr.  A.  A.  Eaton  notes  that  in  the  San 
Joaquin  Valley,  California,  it  is  called  ''  horse-clover  " 
and  is  greedily  eaten  by  horses.  Prof.  C.  E.  Bessey,  how- 
ever, reports  in  the  Fern  Bnlletin  that  it  is  becoming  a 
weed  in  several  wet  meadows  in  Nebraska.  Campbell 
asserts  that  it  is  an  annual,  but  upon  this  point  more 
notes  are  desirable.  Mr.  Eaton  is  of  the  opinion  that 
while  the  leaves  may  die  the  rootstock  does  not.  Like  an 
exotic  species,  Marsilia  Jiirsuta^  it  is  said  occasionally  to 
bear  tuber-like  bodies  on  the  ends  of  certain  branches  of 
the  rootstock,  which  under  proper  conditions  may  pro- 
duce new  plants. 

Marsilia  Macropoda. 

The  species  called  Marsilia  macropoda  is  like  Marsilia 
vcstita  in  being  more  or  less  hairy,  but  it  has  a  longer 
rootstock,  much  larger  leaves,  and  sporocarps  that  are 
borne  in  clusters  of  from  two  to  four  instead  of 
singly.  It  also  probably  lives  longer  than  Marsilia 
vest  it  a. 


Marsilia    Vestita, 


THE  MARSILIAS.  2o[ 

The  rootstock  of  this  species  is  like  that  of  Marsilia 
qiiadrifolia  in  being  wide-creeping.  It  grows  beneath  the 
water  and  sends  up  its  large  leaves  to  the  surface.  These 
are  often  two  inches  or  more  across,  with  deltoid  seg- 
ments having  a  rounded  outer  edge.  Both  sides  bear 
silky  whitish  hairs  that  seldom  fall  off  at  maturity.  The 
sporocarps  are  about  a  quarter  of  ajT  inch  long  and  are 
very  densely  covered  with  long,  tawny,  hair-like  scales. 
The  teeth  are  very  small,  the  lower  one  often  absent. 
There  are  about  twenty  sori  in  each  sporocarp. 

Marsilia  iiiacropoda  has  been  thus  far  found  only  in 
southwestern  Texas  and  New  Mexico.  The  woolly 
nature  of  the  leaves  and  fruit  suggests  that  it  may  be  an 
extreme  form  of  Marsilia  vestita  that  has  been  modified 
by  its  different  habitat.  While  it  is  a  lover  of  water  it 
may  often  be  exposed  to  the  air  by  the  drouths  of  sum- 
mer, and  appears  to  be  most  fruitful  when  growing  with 
the  minimum  of  moisture,  as  do  most  of  the  marsilias. 
Baker  writes  the  specific  name  macropiis. 


Marsilia  Tenuifolia. 


So  far  as  known,  the  plant  called  Marsilia  ienuifolia 
has  been  collected  but  twice,  both  times  in  western 
Texas.  It  has  a  close  resemblance  to  Marsilia  vestita  and 
by  some  is  thought  to  be  a  form  either  of  that  species  or 
of  Marsilia  macropoda.  It  is  described  as  being  slenderer 
than  Marsilia  vestita  with  an  extensively  creeping  root- 
stock.  According  to  Underwood  the  leaves  are  villous 
with  appressed  hairs  and  toothed  on  the  margins  ;  accord- 
ing to  Baker  they  are  nearly  or  quite  smooth,  with 
entire  margins.  The  sporocarps  are  said  to  be  borne 
singly  upon  short  pedicels  and  to  be  tomentose. 


I 


202  THE  MARSILIAS. 

The  plant  has  been  so  seldom  seen  as  to  be  practically 
unknown,  and  it  is  small  wonder  that  the  authorities 
disagree  regarding  it.  Until  we  have  more  definite 
information  it  seems  permissible  to  consider  it  a  form  of 
Mars  ilia  vest  it  a. 


Ma?' si  Ha  Macropoda, 


THE    PiLLWORT. 


THE  PILLWORT, 


IE   only  American  representative 
of   the   genus  Pilulnria  is  that 
rare  little  plant  called  Pilnlaria 
Americana.        In     structure     it 
resembles  a  very  small    species    of 
Marsilia   without   leaf -blades.      It 
grows    among    grasses    and    sedges 
in  wet  places,  but  is  seldom  found 
in  standing  water,  though  it  may  be  in- 
undated at  certain    seasons  of    the   year. 
The    rootstock    is    fine    and     thread-like 
and    creeps    close    to    the     soil,    sending 
down  a  tuft  of  roots  from  each  joint  of 
the  stem,    while    above   rise    the    slender 
leaves.     In  our    plant    these    are    seldom 
more    than  two    inches    long,    are 
very  slender,  and  taper  to  a  point 
like  those  of  the  quillworts.     Like 
the   leaves    of  the    ferns   they  are 
coiled  in  the  bud.     The 
sporocarps  are  borne  on 
short  stalks  in  the  axils 
of  the  leaves   and  are  a 


/i 


2o6  THE  PILLWORT. 

little  more  than  one  twelfth  of  an  inch  in  diameter. 
They  are  round  and  dark  brown  and  contain  four  cells, 
in  each  of  which  is  a  sorus  bearing  megasporangia  and 
microsporangia.  From  the  shape  of  the  sporocarps  this 
plant  gets  its  name  of  '*  pillwort,"  while  an  allied  species 
is  known  abroad,  by  the  name  of  *'  water-pepper,"  from 
the  same  circumstance. 

PihUaria  Americana  has  been  found  in  a  few  localities 
in  California  and  Oregon,  and  is  reported  from  Arkansas 
also.  It  is  quite  likely  that  it  grows  in  many  other 
places  where  its  size  and  shape,  so  much  like  the  imma- 
ture rushes  and  sedges  surrounding  it,  may  aid  it  to  go 
undetected.  This  species  has  also  been  found  in  Chili. 
An  allied  species  is  found  throughout  Europe. 

Mr.  S.  B.  Parish,  writing  of  the  habitat  of  our  species 
in  the  Fern  Bulletifi,  says : 

"  In  winters  of  abundant  rainfall  little  pools  form  in  the  hollows  of 
the  clay  mesas  about  San  Diego,  and  on  the  surface  of  these  pools 
and  on  their  muddy  margins  these  plants  find  a  congenial  home. 
Often  successive  years  pass  with  rainfall  insufficient  to  maintain  these 
pools,  and  consequently  without  affording  the  pilularias  an  opportu- 
nity for  growth." 

The  plants  are  thus  apparently  annuals,  though  all  the 
species  of  Marsiliaceae  are  regarded  as  perennials. 


PILLWORT.     Pihdaria  Americana. 


THE  ISOETACE/E,  OR  QUILLWORTS 


THE  ISOETACE^E, 


HERE  is  doubtless  no  fam- 
ily of  plants  so  little 
known  to  the  botanists 
of  the  regions  in  which 
they  grow  as  the  Iso- 
etaceae,  or  quillworts. 
The  flowers,  fruits,  and  leaves  of  the  flowering-plants 
make  them  conspicuous  ;  the  ferns,  lacking  flowers,  are 
still  noticeable  from  the  beauty  of  their  fronds  ;  and  even 
the  fern  allies,  with  the  present  exception,  may  attract 
attention  by  reason  of  their  strange  forms  and  curious 
manner  of  growth  ;  but  the  quillworts,  most  of  which 
pass  their  whole  existence  beneath  the  waves  of  lake  or 
river,  far  removed  from  the  other  objects  of  the  botan- 
ist's pursuit,  ordinarily  escape  observation,  or,  if  seen, 
are  dismissed  with  the  thought  that  they  are  immature 
specimens  of  some  sedge  or  rush.  Even  the  botanists 
themselves  for  a  long  time  paid  little  attention  to  them, 
usually  referring  such  forms  as  were  found  to  the  single 


210  THE   ISOETACE^. 

species  Isoctes  laciistris.  Although  numerous  species  are 
now  known  to  occur  in  the  waters  of  the  Eastern  States, 
the  eai'ly  volumes  on  the  flora  of  the  region  make  no 
mention  of  them.  Scarcely  fifty  years  have  passed 
since  botanists  began  to  study  these  plants  understand- 
ingly,  and  students  are  yet  by  no  means  agreed  as  to  the 
limits  which  shoulc|  separate  various  species  or  the  posi- 
tion they  should  occupy  as  a  group  in  botanical  classi- 
fication. Baker,  in  his  ''  Fern  Allies,"  places  them  in 
the  Selaginellaceae  ;  Campbell,  in  **  Mosses  and  Ferns," 
considers  them  closely  related  to  such  ferns  as  the 
adder's-tongue  {OpJiioglossuni)  and  the  moonwort  {Botry- 
cJiiiini) ;  while  still  others  believe  that  their  structure 
indicates  a  closer  connection  with  the  pines  and  their 
relatives.  They  are  nowada3's  usually  placed  in  a  sepa- 
rate order,  family,  and  genus,  as  we  have  placed  them 
in  this  volume. 

Notwithstanding  the  close  superficial  resemblance  be- 
tween the  quillworts  and  other  water  vegetation,  the 
difference  between  them  is  quickly  recognised  as  soon  as 
one  has  become  acquainted  with  a  single  species.  A 
quillwort  is  essentially  a  rosette  of  short,  hollow,  cylin- 
drical, pointed  leaves  with  sporangia  in  their  axils.  The 
central  axis  to  which  these  leaves  are  attached  is  short 
and  flat,  so  that  there  is  never"produced  an  elongated 
stem,  as  in  the  other  fern  allies.  If  one  can  imagine  a 
fruit-spike  of  Selaginella  in  which  the  axis  has  failed  to 
develop,  and  in  which  the  sporophylls  have  lengthened 
into  quill-like  though  flaccid  leaves,  he  will  have  a  good 
idea  of  the  typical  quillwort.  The  resemblance  of  the 
plant  body  to  the  bulbs  of  flowering-plants  has  also  been 
frequently  noted. 

The  trunk,  main  axis,  or    rootstock,  though  flat    and 


THE  ISOETACE^. 


211 


tuber-like,  has  a  central  vascular  bundle  surrounded  by  a 
region  of  growing  cells  that  annually  produce  new  bark 
on  one  side  and  add  to  the  vascular  tissue  on  the  other. 
At  two  or  more  points  this  tissue  is  more  active  than  at 
others,  with  the  result  that  mature  rootstocks  are  either 
two,  three,  or  more  lobed.  In  the  hollows  between  these 
lobes,  the  roots  are  given  off,  and  these  are  peculiar  for 
forking  two  or  three  times  like  the  selaginellas,  instead  of 
branching  irregularly  as  those  of  most  plants  do. 

The  leaves  number  from  ten  to  two  hundred  and  are 
arranged  spirally  on  the  upper  part  of  the  rootstock. 
At  the  point  where  they  join  It  they  are  wide 
and  somewhat  triangular  in  cross-section,  but 
above  they  approach  cylindrical  in  form.  In 
length  they  range  from  less  than  two  inches  to 
more  than  two  feet.  Running  lengthwise  through 
the  centre  of  the  leaf  is  a  bundle  of  bast  which, 
with  the  surrounding  tissue, 
separates  the  hollow  interior 
into  four  parallel  chambers 
containing  many  cross-parti- 
tions. In  addition  to  the  cen- 
tral strand  of  bast  there  are  frequently  four 
others,  called  peripheral  bast  bundles,  near  the 
surface.  One  of  these  is  at  the  back  on  the 
outer  side,  another  is  in  the  middle  of  the  inner 
face,  and  the  two  others  are  found  on  either  side 
of  this  on  the  inner  edges  of  the  leaf, 
of  our  species  the  peripheral  bast  bundles  are  ^'"™" 
absent ;  when  two  are  present  they  will  be  found  to  be 
the  dorsal  bundle  and  the  one  in  the  middle  of  the 
inner  face.  The  two  on  the  inner  edge  of  the  leaf  are 
usually  absent. 


Cross-section  of  leaf 
near  base. 


Leaf 

In  most   ^h°^'"^ 

All    iiiKjsL      sporan- 


212  THE  ISOETACE^. 

Only  the  outer  earlier  whorls  of  leaves  produce  sporan- 
gia. When  the  spores  are  ripe  the  fertile  leaves  slowly 
decay,  but  the  sterile,  somewhat  rudimentary  leaves 
remain  green  through  the  winter.  In  the  terrestrial 
species  these  leaves  may  form  somewhat  spiny  processes. 
The  tips  of  ordinary  leaves  usually  end  in  a  long  taper- 
ing point,  which,  with  the  hollow  interior,  is  probably 
responsible  for  the  name  of  quillwort  applied  to  the 
plants. 

The  quillworts  are  usually  about  four  years  old  when 
they  begin  to  bear  spores,  and,  as  might  be  expected, 
their  manner  of  fruiting  shows  most  plainly  their  rela- 
tionship to  the  fern  allies.  Their  resemblance  to  the 
selaginellas  is  particularly  striking,  since  they  bear  two 
kinds  of  spores.  These  are  produced  in  the  axils  of  the 
outer  leaves  in  a  hollowed-out  portion  of  the  leaf.  In 
each  of  these  hollows  is  a  single  oblong  sporangium 
which  may  occasionally  reach  a  length  of  more  than  a 
quarter  of  an  inch.  Over  this  sporangium  the  substance 
of  the  leaf  projects  in  the  form  of  a  thin  indusium  or 
velum,  in  a  few  cases  entirely  covering  the  sporangium, 
but  usually  leaving  a  third  or  more  exposed.  The 
sporangia  are  said  to  be  one-celled,  but  they  contain 
partitions  that  divide  them  into  several  incomplete 
chambers.  This  feature  is  also  found  in  fossil  Icpidoden- 
drons.  Just  beyond  the  sporan^^ium  there  arises  from 
the  inner  surface  of  the  leaf  a  small,  thin,  triangular  flap 
called  the  ligule.  It  is  most  strongly  developed  in  ter- 
restrial forms,  but  its  use  is  unknown.  In  many  species 
some  of  the  cells  in  the  walls  of  the  sporangium  become 
thickened,  giving  it  a  spotted  appearance  which  is  some- 
times considered  of  diagnostic  importance.  The  spots, 
however,  are  not  visible  to  the  unaided  eve. 


THE  ISOETACE^. 


:»3 


The  sporangia  in  the  outermost  leaves  contain  numer- 
ous large  spores  called  megaspores,  macrospores,  or 
gynospores,  while  nearer  the  centre  of  the  plant  similar 
sporangia  bear  a  much  larger  number  of  smaller  spores 
called  microspores  or  androspores.  The  megaspores 
always  produce  female  prothallia,  and  the  microspores 
those  of  the  opposite  sex.  The  megaspores  are  about 
one  fourth  the  size  of  a  pin's  head,  but  are  large  enough 
to  be  seen  with  the  unaided  eye.  Under  a  lens  strong 
enough  to  resolve  their  structure  they  appear  as  spheres 
of  dazzling  white  encircled  by  an  elevated  ridge  near  the 
middle,  called  the  equator,  and  with  three  other  ridges 
called  commissures  going  from  the  equator  to  meet  in 
the  centre  of  the  upper  hemisphere.  One  half  of  the 
spore  is  thus  divided  into 
three  nearly  equal  areas, 
while  the  other  is  with- 
out ridges.  Between  the 
ridges,  especially  on  the 
upper  hemisphere,  the 
surface  is  thrown  into 
many  curious  patterns  in 

which    spines,   crests,    pits,  Megaspores.  (Greatly  enlarged.) 

and  labyrinthine  forms  predominate.  Each  separate 
species  has  its  own  pattern  of  marking,  and  thus  the  spores 
afford  important  characters  for  identification.  The  white 
coating  of  the  spores  has  been  found  by  Mr.  Raynal 
Dodge  to  be  silica,  the  same  flinty  matter  that  gives 
roughness  to  the  stems  of  the  scou ring-rush. 

The  microspores  are  about  one  thousandth  of  an  inch 
in  length  and  very  numerous.  According  to  Dodge 
there  may  be  as  many  as  a  million  spores  in  a  single 
sporangium.    They  are  usually  oblong,  somewhat  triangu- 


214  THE  ISOETACE.E. 

lar  in  cross-section,  and  have  a  smooth  papillose  or  spiny 
surface  mimicking  the  megaspores.  The  size  of  the 
spores  is  usually  given  in  thousandths  of  a  millimeter, 
the  Greek  letter  f^  standing  for  a  single  thousandth. 
Three  hundred  and  fifty  thousandths  of  a  millimeter 
would  be  written  350". 

The  prothallia  of  the  quilhvorts  lack 

'/-^   chlorophyll,  and,  like  the  prothallia  of 

/.;;'^jr  C^^L^A       Sclaginella,  do  not  separate  from   the 

^*^^^^r"^      spores.     At  maturity  the  spore  simply 

Microspores.  opcns    along    the    three    commissural 

(Greatly  enlarged.)  .  .  •  .  i  \  •  i    • 

ridges,  exposmg  the  arcnegonia,  and  ni 
this  position  the  eggs  are  fertilized  by  the*  sperms. 
Some  of  the  aquatic  forms  have  the  power  of  producing 
buds  in  place  of  sporangia,  and  these  finally  float  away 
and  become  new  plants. 

Of  the  fifty  or  more  species  of  Isoetes  a  large  number 
dwell  constantly  on  the  bottom  in  lakes,  ponds,  and 
slow-moving  streams,  at  depths  of  from  one  to  ten  feet 
beneath  the  surface  of  the  water.  Others,  however, 
occur  in  such  situations  that  the  receding  water  in  sum- 
mer exposes  them  to  the  air,  while  a  few  are  rarely  if 
ever  submerged,  though  they  always  grow  in  wet  places. 
Those  that  are  exposed  to  the  air  have  stomata  or 
breathing-pores,  but  those  always  beneath  the  surface 
have  none.  It  is  interesting  to  observe  that  in  those 
species  that  are  only  occasionally  exposed  to  the  air,  the 
stomata  are  found  only  on  the  tips  of  the  leaves,  in  the 
position  where  they  would  be  most  useful  to  the  plant 
should  the  water  leave  any  part  of  it  exposed. 

The  species  of  Isoetes  are  so  much  alike  externally  that 
for  exact  identification  a  compound  microscope  is  neces- 
sary.    An  examination  of  the  ripe  mcgaspores  alone  is 


THE  ISOETACE.€.  215 

usually  sufficient  to  indicate  the  ^roup  to  which  the 
l^lant  belongs,  but  other  considerations  must  often  be 
taken  into  account  in  naming  the  species.  In  the  fol- 
lowing pages,  illustrations  of  the  megaspores  only  have 
been  given.  These  all  have  the  same  magnification,  so 
that  the  comparative  size  of  the  spores  may  be  easily 
seen.  It  is  expected  that  when  the  plants  are  better 
known  than  at  present  the  species  will  be  more  easily 
distinguished,  because  more  accurately  described.  Fur- 
ther notes  on  all  our  species  are  greatly  desired. 

The  word  Isocics  is  said  to  be  derived  from  two  Greek 
words  meaning  **  equal  "  and  "year,"  and  was  applied  to 
these  species  because  of  the  perennial  character  of  the 
leaves.  The  species  are  widely  distributed  throughout 
the  world,  but  are  most  plentiful  in  the  glacial  lakes  and 
the  streams  leading  from  them  in  the  northern  hemi- 
sphere. They  are  an  isolated  group  not  closely  con- 
nected with  any  other  living  forms,  but  exhibiting  in 
their  structure  certain  features  that  seem  to  indicate 
that  the  modern  monocotyledons,  to  which  the  grasses, 
lilies,  and  orchids  belong,  may  have  arisen  from  the 
same  parent  stem.  As  recognised  at  present,  Isoetes  is 
the  only  genus  in  the  family  Isoetaceae,  and  this  family 
the  only  one  in  the  order  Isoetales. 


Key  to  the  Isoetes. 

I.  —  Plants  normally  submerged 

Spores  with  low  tubercles  or  warts,  /.  Bohiftderi 

Spores  with  slender  spines  .  .       /.  echinospora 

Spores  with  short  rounded  crests    .  /.  Macoimi 

Spores  with  worm-like  crests  .     /.  hieroglyphica 

Spores  with  thin  crests  sparingly  anastomosing 

/.  lacustris 
Spores  with  many  anastomosing  ridges 

/.  Tuckertnani 
II.  —  Plants  normally  exposed  in  summer 
Indusium  complete 

Spores  with  fine  warts  .  .      /.  vieIn7iospora 

Spores  with  heavy  tubercles     .  I.Jiaccida 

Indusium  incomplete 

Spores  with  faint  crests  and  warts  /,  Hcnuelli 
Spores  with  numerous  truncate  spines  /.  Gravesii 
Spores  with  spines  and  short  crests 

Mostly  spinulose     .  .        /.  saccharata 

Crests  often  anastomosing  /.  7iparia 

Spores  reticulated 

Ridges  sub-continuous        .       /.  Canadensis 
Ridges  anastomosing 

Ridges  thin     .  .     /.  Engelmanni 

Ridges  moderately  thick  /.  vah'da 

Ridges  very  thick         .         /.  foveolata 
III.  —  Plants  seldom  if  ever  submerged 

Spores  smooth  .  .  .  /.  Orcnffi 

Spores  faintly  warty 

Warts  few  .  .  .  /.  Niittallii 

Warts  many 

Commissures  wide      .      /.  vielanopoda 

Commissures  narrow  .  /.  Buileri 

Spores  with  short  spines     .  .  /.  inininia 


THE  AQUATIC  QUILLWORTS. 


THE  AQUATIC  QUILLWORTS 


SERIES  of  Isoetes  specimens 
could  easily  be  selected  which 
would  show  every  gradation 
from  the  most  deeply  sub- 
merged plants  to  those  habit- 
ually living  in  dry  ground, 
but  such  a  series  would  of  ne- 
cessity include  specimens  of 
many  species.  The  water-loving  species,  however,  keep 
close  to  their  own  element,  and  it  is  only  under  excep- 
tional circumstances  that  they  appear  above  the  surface  ; 
while  the  terrestrial  forms  are  for  a  great  part  of  the 
year  entirely  above  water,  though  growing  in  moist 
places.  Between  these  two  there  are  certain  species 
that  always  live  for  a  part  of  the  year  under  water 
and  a  part  of  the  year  exposed,  so  that  for  purposes 
of  study  it  is  very  convenient  to  divide  the  genus  into 
three  groups  containing  aquatic,  amphibious,  and  terres- 
trial species  respectively,  though  a  hard  and  fast  line 
between  them  cannot  be  drawn.  The  species  of  the  first 
group  have  been  selected  for  description  in  this  chapter. 


Brauns  ^uillwort. 


If,  while  floating  upon  the  quiet  surface  of  some  small 
mountain  lake,  the  collector  should  dis<:ern.  two  or  three 


220  THE  AQUATIC  QUILLWORTS. 

feet  below  the  surface,  a  colony  of  plants  like  small 
green  rosettes,  he  may  conclude  that  he  has  found 
Braun's  quillvvort  {Isoctes  ecJihiospora  Braunii).  Since  all 
the  aquatic  quillworts  have  the  same  general  plan  for  the 
plant  body,  it  is  possible  that  such  a  conclusion  may  have 
to  be  modified  later  and  his  specimens  referred  to  some 
other  species,  but  Braun's  quillvvort  is  so  abundant  and 
so  widely  distributed  that  until  its  spores  have  been  ex- 
amined one  is  fairly  safe  in  assuming  that  any  new  find 
is  this  species. 

The  leaves  are  from  ten  to  thirty  in  number  and  occa- 
sionally reach  a  length  of  ten  inches,  though  the  average 
is  probably  less  than  five.  They  are  dark  green,  occasion- 
ally reddish  at  base,  and  while  in  the  water  are  half  erect. 
When  fresh  from  the  water  they  are  somewhat  rigid  and 
inclined  to  curve  backward.  There  are  a  few  stomata 
present  on  the  tips  of  the  leaves,  but  the  peripheral  bast 
bundles  are  absent,  as  is  usual  in  the  submerged  species. 
The  sporangium  is  pale  spotted,  and  the  velum  or  in- 
dusium  about  half  covers  it. 

The  principal  distinguishing  charac- 
ter is  found  in.  the  megaspores.  These 
are  from  350 /"  to  550/^  in  diameter  and 
covered  with  broad  spinules  which  are 
often  forked  or  toothed  and  sometimes 
recurved.  Occasionally,  too,  the  spin- 
ules may  become  confluent  into  short 
Megasporeof         crcsts.     The  microsporcs  are  from  26/^ 

Isoetes  echinospora 

Braunii.  ^q    30 /^    in    length,    white   or    grey  in 

colour,  smooth,  and  very  numerous.  Three  hundred 
thousand  microspores  have  been  found  in  a  single 
sporangium.  The  spores  retain  their  vitality  for  some 
time,  and  plants  have  been  raised  from  the  spores  taken 
from  herbarium  specimens. 


BRAU  N  'S  QU I L LWORT.     Isoetes  echinospora  Braimu. 


THE  AQUATIC  QUILLWORTS.  221 

The  typical  Isoctcs  ecJiinospora  is  an  Old  World  species 
found  in  the  lakes  of  northern  and  central  Europe.  It 
differs  from  our  plant  in  having  an  unspotted  sporangium, 
a  narrower  indusium,  and  no  stomata.  These  differences 
have  been  considered  sufificient  to  make  our  plant  a  sepa- 
rate variety.  There  can  scarcely  be  a  doubt  that  the  two 
forms  have  arisen  from  a  common  ancestor.  Our  plant 
holds  the  same  position  in  North  America  that  the  type 
does  in  Europe.  In  the  "Ferns  and  Fern  Allies  of  New 
England,"  Dodge  gives  its  habitat  as  ''margins  of  ponds 
often  wholly  submerged  ;  also  on  the  muddy  shores  of 
streams  or  on  the  tidal  tracts  of  rivers,  often  where  the 
water  is  very  brackish."  The  author  has  seen  it  in  many 
of  the  small  glacial  lakes  of  northern  Pennsylvania,  but  he 
has  never  collected  it  in  a  locality  in  which  it  was  ever 
likely  to  be  above  water.  There  seems,  therefore,  to  be 
some  difference  in  its  habitat  in  different  parts  of  its  range. 
The  fact  that  it  bears  stomata  may  be  taken  as  an  indica- 
tion that  it  is  prepared  for  an  occasional  exposure  to  the 
air. 

Our  plant  ranges  from  Pennsylvania,  Utah,  and  Wash- 
ington to  Alaska  and  Greenland.  Ac- 
cording to  Baker  it  is  also  found  in 
Iceland.  The  American  plant  has 
several  forms  or  varieties.  A  stouter 
plant  with  more  numerous  leaves  and 
abundant  stomata  is  called  the  variety 
robtista,  and  a  form  with   long  slender 

1  ^1  -'111.1  ]Mej,'aspore  of 

spmules  on  the  megaspores  is  called  the      isoeus  echinospora 

,-,  .  .  .  vniricnta. 

variety  Boottii.     Kobiista  is  recorded  as 
growing  in  Vermont  and   New  Hampshire,   and  Boottii 
has   never  been   found    except  in    the    few  localities   in 
Massachusetts  where  Boott  first  found  it.     These   forms 


THE  AQUATIC  QUILLWORTS. 


Megaspore  of 

Isoetes  ech  inosporc 

Flettii. 


appear  to  be  trivial  ones  produced  by  the  habitat  in 
which  they  grow.  Most  botanists  now  give  little  atten- 
tion to  them.  According  to  Eaton  Boottii  is  found  in 
sand,  and  this  may  account  for  its  characteristic  slender 
leaves. 

Isoetes  ecJdnospora  imiricata  is  a  more  pronounced  form. 
The  leaves  are  longer,  slenderer,  and 
inclined  to  be  spiral  and  the  mega- 
spores  are  slightly  larger,  and  covered 
with  shorter,  thicker,  and  more  con- 
fluent spinules.  In  deep  water  the 
slender  leaves  are  inclined  to  take  on 
a  spiral  form.  This  variety  is  found 
from  Nova  Scotia  to  New  Jersey. 
Isoetes  ecJdnospora  Flettii  comes  from  a 
few  lakes  in  Washington  and  British 
Columbia,  and  differs  from  the  type  in  having  stout 
leaves,  and  the  spines  of  the  megaspores  few,  very  short, 
almost  wart-like.  This  is  an  extreme  form  and  by  some 
might  be  considered  a  distinct  species.  In  spore  char- 
acters it  approaches  the  various  other  species  of  the 
Northwest,  and  except  for  the  size  of  the  spores  might 
be  considered  a  variety  of  Isoetes  Bolanderi, 

A  stout  plant,  also  from  northwestern 
America,  has  been  named  Isoetes  ecJiino- 
spora  truneata.  This  has  megaspores 
thickly  covered  with  short  truncate 
columns.  The  spores  are  noticeably 
flattened  on  the  hemispheres  contain- 
ing the  commissures,  and  are  not 
easily  confused  with  those  of  other 
species.  This  form  is  reported  from  Vancouver  Island 
to  Alaska,  but  is  as  yet  not  common.    The  author  would 


Megaspore  of 
Isoetes  truneata. 


THE  AQUATIC  QUILLWORTS.  223 

be  inclined  to  call  this  a  distinct  species  and  to  name  it 
Isoctcs  t  rune  at  a. 

In  1888  Underwood  described  anew  species  from  speci- 
mens collected  on  Vancouver  Island,  to  which  he  gave 
the  name  of  Isoctcs  niaritiina.  This,  Mr.  Eaton  is  con- 
vinced, is  but  a  variety  of  Isoctcs  cc]iinospora.  When  it 
was  described  it  was  supposed  to  be  a  terrestrial  species, 
and  the  resemblance  of  its  megaspores  was  not  considered 
important  ;  but  inquiries  of  the  collector  having  since 
shown  that  it  is  regularly  inundated  by  the  tide,  Mr. 
Eaton  seems  warranted  in  calling  it  Isoctcs  ccJiinospora 
maritima.  It  is  described  as  having  from  eight  to  twelve 
rigid  leaves  one  to  two  inches  long.  The  megaspores 
are  covered  with  rather  thick,  bluntish  spines. 

In  many  lakes  and  ponds  Isoctcs  ecJiinospora  and  its 
varieties  form  an  almost  unbroken  carpet  over  large 
areas,  the  width  depending  upon  the  rate  with  which 
the  water  deepens,  being  widest  in  shallow  ponds  and 
ending  usually  when  depths  of  three  or  more  feet  are 
reached.  It  grows  either  in  sand  or  mud,  though  it  is 
said  to  prefer  mud,  and  is  most  luxuriant  where  exposed 
to  the  sunlight.  It  appears  to  be  also  fairly  abundant  in 
certain  rivers,  usually  only  where  it  is  covered  with 
water  most  of  the  time.  Until  one  has  become  accus- 
tomed to  its  appearance  it  is  often  likely  to  be  mistaken 
for  the  other  water  plants  with  which  it  grows.  Should 
our  common  plant  ever  be  considered  distinct  from  the 
European  species  it  would  have  to  have  a  new  name, 
since  Braiinii  is  preoccupied  as  a  specific  name.  Braun 
has  suec^ested  that  in  this  event  it  be  called  Isoctcs  am- 
bigiia.  The  crisp  bulbs  of  this  species  are  favourite  mor- 
sels with  muskrats,  and  cattle  are  said  to  feed  upon  the 
leaves  of  any  species  that  are  accessible. 


224  THE  AQUATIC  QUILLWORTS. 

T^he  Lake  ^luillwort. 

The  lake  quilhvort  {Isoetcs  lacustris)  was  not  named 
because  it  is  the  typical  quilhvort  of  our  lakes,  but  be- 
cause it  was  first  found  and  is  quite  abundant  in  the  lakes 
of  Europe.  There  are  good  botanists 
who  doubt  that  it  has  ever  been  found 
in  America,  though  it  was  often  re- 
ported by  early  collectors.  At  that 
time,  however,  it  was  customary  to 
refer  all  our  plants  to  Old  World  species 
Me^aspore  of         of  similar  appcarauce,  and  this  probably 

Isoetes  lacustris.  i     •  j_i  i^  r    • . 

explauis  the  many  reports  of  its  occur- 
rence in  regions  where  nowadays  it  cannot  be  found. 

Isoetes  lacustris  is  described  as  having  from  ten  to 
thirty  dark-green  leaves  from  three  to  six  inches  long. 
There  are  no  stomata  in  the  leaves,  and  the  indusium  cov- 
ers about  one  third  of  the  unspotted  sporangium.  The 
megaspores  are  from  500^  to  800 /"  in  diameter,  marked 
all  over  with  short,  thin,  wavy  ridges.  The  microspores 
are  35  /^  to  45  /"  long,  light  grey,  and  smooth.  The  Ameri- 
can plant  differs  from  the  European  in  the  larger  mega- 
spores, and  Durieu  proposed  that  it  be  called  Isoetcs 
viacrospora.  It  would  seem  wise,  in  view  of  the  appar- 
ent absence  of  true  Isoetes  lacustris^  to  refer  all  our  plants 
to  Isoetes  inacrospora.  Mr.  A.  A.  Eaton  concurs  in  this 
opinion,  but  since  Isoetes  lacustris  has  long  had  a  place  in 
our  flora  we  have  here  included  Isoetes  inacrospora  with  it. 

The  typical  Isoetes  lacustris  is  spread  widely  through 
the  lakes  of  northern  Europe,  and  is  well  enough  known 
to  receive  the  common  name  of  ''  Merlin's  grass."  It 
grows  in  from  one  to  six  feet  of  water.  Fish  are  said 
to  be  fond  of  the   tender  leaves,  and  are  reported  some- 


THE  AQUATIC  QUILLWORTS.  225 

times  to  root  them  up.  The  fleshy  corms  or  rootstocks 
have  occasionally  been  eaten  in  Europe,  but  are  said  to 
have  an  eartliy  taste  that  is  scarcely  palatable.  The 
American  range  of  this  species  is  given  as  from  New 
Jersey,  Lake  Superior,  Colorado,  and  California  north- 
ward. The  plant  originally  described  by  Engelmann  as 
Isoetes  laciistris,  \di\-\(ity  pauper cu la,  is  considered  by  Mr. 
Eaton  as  entitled  to  specific  rank.  It  has  fewer,  thinner, 
and  shorter  leaves  and  smaller  spores.  It  is  found  in 
Colorado  and  California.  This  form  was  also  collected 
by  Henderson,  who  named  it  Isoetes  occidentalis. 

"Tuckermari s  ^luillwort. 

In  Tuckerman's  quillwort  {Isoetes  Tiickennani)  we  have 
a  plant  with  much  the  habit  of  Braun's  quillwort,  but 
with  spore  characters  that  link  it  more  closely  with 
Isoetes  lacustris  and  Isoetes  riparia.  It  may  be  distin- 
guished at  sight,  however,  by  the 
leaves,  which  are  very  slender  and 
tinged  with  red.  They  are  from  two 
to  five  inches  long  and  usually  spirally 
twisted.  It  was  long  thought  that  this 
species  lacks  stomata,  but  it  is  now 
known  occasionally  to  bear  them 
in  small    numbers,  especially  if  e^row-  Megasporeof 

^  Isoetes  Tucker vuini. 

ing  in  situations  where  they  may  be 
exposed  to  the  air.  The  sporangia  are  small,  sparingly 
pale  spotted,  and  the  upper  third  is  covered  by  the  in- 
dusium.  The  megaspores  are  450^  to  560/'  in  diameter, 
marked  with  parallel  and  anastomosing  ridges  on  the 
upper  segments,  and  somewhat  more   reticulated   below. 


226  THE  AQUATIC  QUILLWORTS. 

Ill  New  Hampshire,  Mr.  Eaton  has  discovered  plants  in 
which  the  spores  were  of  various  diameters  up  to  750/^ 
but  otherwise  like  the  type.  The  microspores  are 
smooth  and  26/"  to  32/"  long. 

So  far  as  known,  Tuckerman's  quillwort  is  confined  to 
the  New  England  States.  It  was  formerly  considered 
rare,  but  a  more  careful  study  of  the  material  has  shown 
that  much  of  what  was  once  referred  to  Isoetes  lacustris 
and  Isoetes  riparia  really  belong  to  this  species.  Mr.  A. 
A.  Eaton  asserts  that  within  its  range  it  is  likely  to 
occur  in  any  large  pond  with  sandy  shores,  especially  if 
a  little  silt  has  been  deposited  upon  the  sand.  It  grows 
in  from  one  to  four  feet  of  water,  forming  extensive 
colonies,  and  is  rarely  found  in  situations  where  the 
water  is  not  at  least  a  foot  deep  during  the  drouths  of 
summer.  The  depth  at  which  it  grows  suggests  the 
possibility  that  the  red  colouring-matter  in  the  leaves 
may  aid  in  assimilation,  just  as  the  same  colour  is  known 
to  do  in  the  red  seaweeds. 

Plants  from  Maine  and  New  Hampshire,  in  which  the 
leaves  are  longer  and  stouter,  have  been  named  the 
variety  borealis.  This  is  said  to  have  enough  likeness  to 
plants  of  Isoetes  lacustris  to  be  almost  entitled  to  rank 
as  a  form  of  that  species.  Still  another  form,  described 
as  Isoetes  Harveyi,  has  recently  been  found  in  Maine.  In 
this  the  leaves  are  stout  and  very  numerous,  often  one 
hundred  or  more,  though  less  than  three  inches  in 
length.  The  sporangia  are  small,  unspotted,  and  about 
one-third  indusiate.  The  megaspores  are  525  ^  to  650/^ 
in  diameter,  but  may  occasionally  be  found  of  diameters 
up  to  800/^.  The  spores  are  similar  to  those  of  typical 
Tiickerinani,  but  the  leaves  are  very  different.  In  the 
opinion  of   the    describer,  however,  it   is  not  sufficiently 


THE  AQUATIC  QUILLWORTS.  227 

distinct  to  be  called  a  species,  and    it  has  recently  been 
reduced  to  a  variety  of  Isoetes  Tucker niani. 

Under  the  name  of  Isoetes  Jieterospora  Mr.  A.  A. 
Eaton  has  described  a  species  from  Mount  Desert 
Island,  Maine,  which  the  author  would  be  inclined  to 
call  a  form  of  Isoetes  Tttckennani  also.  In  this  form  the 
leaves  are  two  or  three  inches  long,  from  fifty  to  seventy- 
five  in  number,  and  lack  stomata.  The  sporangia  are 
thickly  spotted  and  are  one  third  or  more  indusiate. 
The  megaspores  are  normally  540/^  to  675/"  in  diameter, 
but  specimens  with  a  diameter  of  1150/^  are  often  found. 
They  are  densely  covered  with  thick,  jagged,  anastomos- 
ing crests,  often  honeycombed  below.  The  microspores 
are  30/^  to  40^  in  length,  dark  brown,  and  papillose.  The 
megaspores  often  have  neither  commissures  nor  equato- 
rial ridge.  Occasionally  what  answers  to  the  latter  is 
present,  but  misplaced,  often  enclosing  but  a  small  area 
on  one  side  of  the  spore.  This  seems  to  indicate  an 
aberrant  plant.  Thus  far  it  has  been  found  in  but  two 
localities,  both  on  Mount  Desert  Island,  Maine. 

Bo  lander  s   ^uiilwort. 

In  the  western  part  of  America  the  lakes  occasionally 
contain  a  species  of  Isoetes  called  Bolander's  quill  wort 
{Isoetes  Bolanderi),  which  by  the  single  item  of  the  spore 
markings  may  be  separated  from  all  our  Eastern  species. 
In  its  own  region,  however,  it  is  easy  to  confuse  with 
other  species,  which  are  marked  much  like  it.  In 
appearance  this  species  has  a  resemblance  to  the  mem- 
bers of  what,  for  convenience,  may  be  called  the  Isoetes 
ecJiinospora  group.  Its  leaves  are  erect,  bright  green, 
from  five  to  twenty-five  in  number,  and  from  two 
to  four  inches  long.     They  generally  have   few   stomata 


228  THE  AQUATIC  QUILLWORTS. 

and    no    peripheral    bast    bundles.     The    sporangia    are 
broadly    oblong    or    elliptical,    and    sparingly    spotted. 
The  megaspores  are  300 '^   to   450^   in   diameter,  marked 
with  small  dots  or  warts  which   rarely  run 
together   to   form  wrinkles.       The  micro- 
spores are  deep   brown,  26/^  to  31 '^  long, 
spinulose  or  rarely  smooth.     This  species 
is  found  in  western  Colorado,  Utah,  and 
Megaspore  of        California,  and  grows    in  streams  as  well 
isoeies Boian.ieri.     ^^  j^^  ponds.     The  form  Called  Sonnei  was 

described   from  plants  collected   at   Donner  Lake,  Cali- 
fornia. 

In  1866,  Bolander,  after  whom  this  species  was  named, 
found  at  Mono  Pass,  on  the  eastern  slope  of  the  Sierra 
Nevada,  at  an  altitude  of  7,000  feet,  a  peculiar  form 
which  has  since  been  known  as  Isoetes  pyguKEti.  Its 
resemblance  to  Isoetes  Bolanderi  is  so  marked  that  there 
should  be  no  doubt  of  their  being  two  forms  of  the  same 
species.  The  principal  difference  is  that  the  plants  of 
Isoetes  pygnicea  have  shorter  leaves,  seldom  reaching  an 
inch  long.  The  microspores  also  are  less  spinulose.  To 
the  author  this  seems  but  a  mere  form  of  the  better- 
known  species,  and  he  would  call  it  Isoetes  Bolanderi 
pygmcea.  Its  small  size  is  undoubtedly  due  to  its  place 
of  growth  in  a  cold  mountain  stream.  The  megaspores 
are  exactly  like  those  of  Isoetes  Bolanderi^  only  a  trifle 
smaller.  It  has  been  collected  but  once,  though  often 
searched  for  during  the  past  half  century. 

Isoetes    Hieroglyphica. 

From  certain  lakes  in  Maine  have  been  collected 
specimens  of  an  Isoetes  which,  to  judge  from  spores 
alone,  is  distinct  from  all  others.     This  has  recently  been 


THE  AQUATIC  QUILLWORTS.  229 

named  Isoctcs  Jiicroglyphica.      It   is  described   as    having 

ten   to  twenty  leaves    two  or  three  inches  long,  which 

are    recurved    and    somewhat    blunt    at    the     tip.     The 

sporangium  is  unspotted  and  about  one  third  indusiate. 

The  megaspores  are  very  characteristic, 

being  from  485/"  to  590/^  in   diameter, 

and  marked,  except   near  the  equator, 

with  rather  large  wormlike  ridges.    The 

body  of  the  spore  is  quite  smooth  and 

greyish    in    colour.     The    microspores 

are  from  31  /"  to  44/^  \ox\^  and  are  warty. 

^  ^^  5^  -^  Megaspore  of 

In  outward  appearance  the   plant   has      i^ortes hierogiyphica. 
great    resemblance   to  Isoetes  Tuckennani,  to  which  it  is 
no  doubt  closely  related,  though  tlie  spore  characters  are 
distinctive. 

Isoetes  Macount. 

Isoetes  Macoitni  is  known  to  grow  only  on  Atka  Island, 
off  the  coast  of  Alaska,  from  whence  it  was  brought  by 
J.  M.  Macoun  in  1891.  The  plants  were  found  in  a 
pool  on  the  side  of  an  extinct  volcano,  and  apparently 
in  such  a  position  as  to  be  always  submerged.  The 
leaves  are  from  five  to  twelve  in  number, 
about  two  inches  long,  and  quite  stout. 
The  megaspores  average  about  450/^  in 
diameter  and  are  set  with  stout  blunt 
spinules  usually  about  twice  as  long  as 
broad.     The    microspores   are   finely  and 

Megaspore  of  ^  -^ 

Isoetes Macouni.  dcuscly  papillose  and  about  40/^  long.  It 
is  possible  that  this  is  still  another  form  of  Isoetes  ecJiino- 
spora.  It  has  considerable  resemblance  to  the  variety 
Flettii,  and  the  differences  it  presents  may  be  due  to  its 
habitat. 


THE  AMPHIBIOUS  QUILLWORTS 


THE  AMPHIBIOUS  QUILLWORTS, 


HE  aquatic  quilhvorts  are  naturally 
found  in  lakes  and  ponds,  since  few 
other  situations  present  the  unvary- 
ing water-level  and  other  conditions 
favourable  to  their  growth.  The 
amphibious  quilKvorts,  on  the  con- 
trary, are  more  frequently  to  be  found  along  rivers  and 
streams  where  the  receding  waters  leave  them  exposed 
to  the  air  fOr  at  least  a  part  of  the  summer.  The  few 
members  of  this  group  that  grow  in  lakes  and  ponds  are 
to  be  found  close  to  the  margin,  in  which  situations  they 
are  usually  above  the  water  for  a  part  of  the  summer  at 
least. 

Engelmann  s  ^luillwort. 

Among  American  students  of  the  Isoctes  there  are  few 
whose  names  are  more  closely  associated  with  the  genus 
than  that  of  the  late  Dr.  George  Engelmann,  of  St. 
Louis,  and  it  is  most  fitting,  therefore,  that  the  species, 
Isoetes  Engebnanniy  which  commemorates  his  name, 
should  be  both  common  and  widely  distributed. 

This  species  may  at  once  be  distinguished  from  the 
aquatic  quilhvorts  by  its  much  longer  leaves.  In  the 
quiet  waters  of  lake  and  pond  the  leaves  of  the  quill- 
worts  are  inclined  to  be  short  and  arranged  in  a  distinct 


234  THE  AMPHIBIOUS  QUILLWORTS. 

rosette  ;  but  in  rivers  where  the  species  are  exposed  to 
more  or  less  current  the  leaves  are  likely  to  be  longer, 
and,  though  arranged  in  circles,  the  rosette  appearance 
is  often  obscured  because  the  flaccid  leaves  all  extend  in 
the  direction  taken  by  the  current.  In  the  present 
species  the  leaves  are  sometimes  up- 
ward of  a  hundred  in  number  and 
twenty  or  more  inches  long.  Ordinary 
forms,  however,  are  usually  less  than  a 
foot  in  length.  Being  exposed  to 
the  air  for  a  large  part  of  the  year,  the 
Megasporeof  leaves     have    abundant    stomata,  and 

Jsoetes  ±.ngeli)ia7im.  ' 

the  peripheral  bast  bundles  necessary 
to  give  strength  to  the  aerial  leaves  are  also  present. 

The  plants  usually  grow  on  the  margins  of  streams. 
During  winter  and  spring  they  are  covered  by  the 
water,  but  as  the  waters  diminish  with  the  warm 
weather  the  leaves  are  soon  exposed  to  the  air,  either 
by  floating  on  the  surface  of  the  shallow  water  or  by 
being  left  entirely  exposed.  The  leaves  found  early  in 
spring  are  the  ones  that  bear  the  sporangia.  They  are 
long  and  flaccid,  and  upon  exposure  to  the  air  are  likely 
to  decay,  being  replaced  by  circles  of  shorter  recurved 
leaves,  some  of  which,  if  the  season  is  long  enough,  may 
also  perfect  sporangia.  It  is  probable  that  these  leaves 
are  normally  sterile  and  alternate  with  the  fertile  leaves. 

The  sporangia  are  unspotted  and  have  a  narrow  in- 
dusium.  The  spores  are  released  by  the  decay  of  the 
sporangium,  and  for  some  time  after  the  leaves  have 
fallen  the  sporangia  may  be  found  attached  to  the  plant. 
The  megaspores  are  from  350 /"  to  550/^  delicately  honey- 
comb reticulated.  The  microspores  are  24/^  to  28^  in 
length,  and  nearly  smooth.     In  the  southern  parts  of  this 


ENGELMANN'S  QUILLWORT.     Jsoetes  Engel. 


inanm. 


THE  AMPHIBIOUS  QUILLWORTS. 


235 


Meg^aspore  of 

Isoctes  Engelmanni 

Caroliniana. 


species'  range  the  spore-markings  are  less  constant  and 
the  species  breaks  up  into  varieties.  The  variety /<?;//^;2^, 
distinguished  from  the  type  by  having  many  stomata,  four 
or  more  peripheral  bast  bundles,  and  a  spotted  sporan- 
gium, has  been  reported  from  eastern  Pennsylvania.  A 
very  slender  form,  with  about  a  dozen 
leaves,  often  found  with  the  type,  is 
named  variety  gracilis.  It  is  probably 
due  to  plants  growing  in  deep  water  or 
in  dense  shade.  The  variety  Georgiana 
has  few  leaves  and  slightly  larger  mega- 
spores.  More  pronounced  is  the  form 
from  North  Carolina  described  as 
Isoetcs  Engelniajini  Caroliniana.  In 
this  the  leaves  and  indusium  are  slightly  broader,  and 
the  megaspores  are  marked  by  thin  and  broken  crests 
which  often  present  spinules  like  those  of  Isoetes  ecJiino- 
spora  and  have  few  if  any  reticulations.  The  microspores 
also  are  slightly  larger  and  densely  spinulose. 

Isoetes  Engelmanni  is  found  most  abundantly  on  the 
gravelly  shores  of  rivers  and  streams.  Eaton  says  that 
in  New  England  it  is  very  common  in  clay  soil  in 
ponds  and  ditches,  but  rarely  occurs  in  mud  and  sand. 
In  parts  of  New  Hampshire  it  is  reported  as  common  in 
nearly  every  millpond  and  ditch  with  a  clay  bottom.  It 
is  likely  that  the  plants  growing  in  ponds  are  seldom 
above  water,  which  shows  how  arbitrarily  the  amphibi- 
ous group  of  quillworts  has  been  constituted.  The 
species  ranges  from  Maine  to  Delaware,  Pennsylvania,  and 
Missouri.  The  variety  Georgiana  is  found  only  in  the 
State  for  which  it  is  named.  Isoetes  Engelmanni  Carolin- 
iana has  been  found  in  several  localities  in  North  Caro- 
lina. 


236  THE  AMPHIBIOUS  QUILLWORTS. 

Raton  s  ^luillwort. 

In  1867  Engelmann  described  a  gigantic  species  of 
quillvvort  from  eastern  America,  which  he  considered  a 
form  of  Isoetcs  Engelmanni  and  to  which  he  gave  the 
name  of  Isoetcs  Engelinan?ii  valida.  It  is  described  as 
having  from  fifty  to  two  hundred  leaves  two  feet  or  more 
long,  springing  from  a  very  massive  trunk,  and  is  in  fact 
the  largest  form  of  Isoetes  in  America,  if  not  in  the 
world.  It  has  never  been  reported  from  New  England, 
but  within  recent  years  there  has  been  discovered  in  that 
region  an  equally  large  quilhvort  which  has  been  named 
Isoetcs  Eatoni.  These  forms  are  so  nearly  alike  as  to 
suggest  that  they  are  two  forms  of  the  same  species.  If 
valida  is  really  different  from  Eatoni  and  a  mere  form 
of  Isoetcs  Engelmanni,  it  is  not  easily  explained  why  it 
does  not  occur  in  New  England,  where  the  species  is  so 
common.  The  fact  that  Isoetcs  Eatoni 
is  confined  to  New  England  seems  to 
indicate  that  this  is  the  New  England 
counterpart  of  valida.  When  the  New 
England  form  was  discovered  it  was  con- 
Meg^I^reof  sidcrcd  a  distinct  species,  and  in  this 
Isoetes  valida.  Qpij-jion  the  author  concurs.  As  a  species, 
however,  it  should  be  known  as  Isoetcs  valida,  since  this 
varietal  name  was  given  before  that  of  Isoetes  Eatoni. 

The  trunk  of  this  form  is  occasionally  four  inches  in 
diameter,  and  the  leaves  have  been  knowi}  to  reach  a 
length  of  twenty-eight  inches.  The  summer  leaves  are 
usually  much  shorter,  often  under  six  inches  long.  The 
peripheral  bast  bundles  are  usually  present,  though  weak, 
and  there  are  abundant  stomata.  The  sporangia  are  re- 
markably  large,   frequently  half  an  inch   long,   but    the 


THE  AMPHIBIOUS  QUILLWORTS.  237 

megasporcs,  curiously  enough,  arc  smaller  than  the  aver- 
age, being  from  300/^  to  450/'  in  diameter.  The  mega- 
spores  of  Isoetes  Eatoni  are  described  as  being  marked 
with  ''  convolute  labyrinthiform  ridges,  cristate  on  the 
angles  of  the  inner  face."  The  markings  of  the  spores 
alone  are  nearly  sufficient  to  constitute  this  a  good 
species.  They  appear  like  those  of  Isoetes  Engelmanni, 
in  which  many  of  the  connecting  crests  have  disappeared. 
The  fact  that  the  so-called  variety  valida  is  described  as 
having  spores  smaller  than  the  type  is  also  significant. 
Mr.  Eaton,  who  has  made  a  very  careful  study  of  this 
genus,  is  of  the  opinion,  however,  that  the  two  forms  are 
not  identical. 

If  we  consider  them  two  forms  of  one  species  the 
range  may  be  given  as  from  New  Hampshire  to  Dela- 
ware and  Virginia.  The  plant  is  rare,  however,  and  has 
been  found  only  in  a  few  localities  within  this  territory. 
A  curious  thing  about  the  plants  from  New  England  is 
that  they  appear  to  be  dioecious.  Microspores  are  seldom 
found,  but  the  megaspores  are  abundant.  It  is  surmised 
that  the  same  sporangium  may  occasionally  bear  both 
kinds  of  spores,  as  is  sometimes  the  case  in  Isoetes  Tuck- 
er in  an  i. 

Isoetes  Canadensis. 

The  history  of  the  quillwort  now  called  Isoetes  Cana- 
densis is  a  good  illustration  of  the  way  small  and  easily 
overlooked  differences  may  affect  our  conception  of 
species  in  the  genu?,  Isoetes.  It  was  first  called  the  variety 
Canadensis  of  Isoetes  riparia.  Later  the  same  species  was 
found  in  New  England,  and,  its  identity  being  overlooked, 
it  was  described  as  Isoetes  Dodgei.     The  name  first  given 


23^  THE  AMPHIBIOUS  QUILLWORTS. 

to  the  plant  of  course  liolds  good,  and  since  it  seems  cer- 
tain that  this  is  a  separate  species  it  is  therefore  properly 
called  Isoetes  Canadensis.  For  some  time,  however,  the 
name  of  Isoetes  Dodgei  is  the  one  it  has.  commonly  borne. 
In  appearance  Isoetes  Canadensis  is  much  like  Isoetes 
Engehnanni.  The  leaves  are  from  eight  to  fifteen  inches 
long,  often  seventy-five  in  number,  and  when  under 
water  are  half  erect  and  inclined  to  twist.  The  leaves 
that  appear  in  summer  are  sliorter,  as  usual.  The  spor- 
angia are  about  one  fourth  indusiate  and  spotted.  The 
megaspores  are  500  "  to  675,"  in  diameter,  with  irregular, 
low,  sub-continuous,  thin  crests  scat- 
ered  over  them.  The  hemisphere  that 
bears  the  commissures  is  decidedly 
flattened,  and  the  commissures  them-^ 
selves  are  inclined  to  produce  thin, 
short,  lateral  projections.  In  appear- 
Meg^^reof  auce  the  spores  suggest  the  spores  of 
/.../..  Canadensis,      j^^^^^^  Engebnanni,  in  which  the  crests 

have  so  nearly  disappeared  that  vestiges  of  only  the 
heaviest  remain.  The  microspores  are  22  /^  to  40"  long, 
ashy  in  colour,  and  wrinkled. 

Mr.  Eaton  has  described  a  variety  of  this  species  from 
Massachusetts,  in  which  the  leaves  contain  four  bast 
bundles  and  are  rather  stiff  and  erect,  even  when  out  of 
the  water.  To  this  the  varietal  name  of  Robbinsii  has 
been  given.  The  megaspores  are  described  as  being 
thickly  beset  with  anastomosing  jagged  walls,  much  as  in 
Isoetes  riparia,  though  thicker.  A  variety,  Avtesii,  of 
Isoetes  saeeharata,  appears  to  be  enough  like  Robbinsii  to 
be  classed  with  it.  So  intermediate  are  the  characters 
that  distinguish  Robbinsii  that  it  might  with  equal  pro- 
priety   be  regarded    as  a  variety    of  Isoetes   riparia    or 


THE  AMPHIBIOUS  QUILLWORT.  239 

of  Isoctcs  Canadensis ;  but  it  is  probcible  that  Isoctcs 
riparia  does  not  occur  in  New  England.  This  is  doubt- 
less the  plant  that  has  so  frequently  been  mistaken  for 
that  species  in  this  region. 

Isoctes  Canadensis  has  been  found  in  various  localities 
from  Maine  to  Pennsylvania,  and  also  in  Ontario  and 
British  Columbia.  It  is  doubtless  more  abundant  than 
it  is  at  present  known  to  be.  It  grows  in  shallow  water 
in  rivers. 

T'he  River-Bank    ^uillwort. 

The  river-bank  quillwort  {Isoctes  riparia)  was  found  near 
Philadelphia  by  Nuttallin  181 5,  but,  as  was  usual  in  those 
days,  it  was  referred  to  the  common  European  Isoetes 
lacnstris,  and  it  was  not  until  thirty  years  afterward  that 
its  distinctness  was  recognised  and  the  name  it  now 
bears  was  assigned  to  it. 

Isoetes  riparia  is  a  medium-sized  species  with  from 
fifteen  to  thirty  round  leaves  that  oc-  ^^^Sr^S^X, 
casionally  reach  a  length  of  a  foot,  but 
are  commonly  several  inches  shorter. 
The  leaves  have  abundant  stomata,  are 
without  bast  bundles,  and  the  sporangia 
are  spotted  and   about  one  third  indu- 

.     .  /-pii  ,       x-  Meefaspore  of 

Slate.  1  he  megaspores  are  450  /«  to  650  f^  isocus  riparia. 
in  diameter,  with  thin,  jagged,  irregular  crests  that  so 
nearly  resemble  those  of  both  Isoetes  lacustris  and 
Isoetes  Tiickerniani  that  good  students  of  the  genus  can- 
not always  agree  as  to  their  identity.  They  may  usually 
be  distinguished  from  Isoetes  Tuckerniani,  however,  by 
the  crests  being  more  numerous,  thicker,  and  longer, 
and  from  Isoetes  lacnstris  by  the  crested  commissures. 


240  THE  AMPHIBIOUS  QUILLWORTS. 

The  true  Isoctcs  riparia  has  apparently  never  been 
found  anywlierc  except  along  the  lower  Delaware, 
though  often  reported  from  other  localities. 

Isoetes  Saccharata. 

This  was   formerly  supposed   to  be  a  distinct  species, 

but  additional  collections  and  further  study  have  shown 

it  to  be  so  nearly  like  Isoetes  riparia  that  it  is  now  often 

suggested  that  they  are  two  extreme 

forms  of  the  same  species.     Not  only 

are  typical  plants  very  much  alike,  but 

various  intergrading  forms  have   been 

found.     Notwithstanding  this,    it   will 

be  retained  as  a  species  here,  in  order 

Megasporeof  uot  to  coufuse  the  beginner,  who  will 

Isoetes  saccharata.  r       ^    ' ,  ,       i    •  \         .  i  i 

find  it  so  treated  in  the  text-books. 

The  leaves  are  from  ten  to  twenty  in  number,  dark 
green,  slender,  and  from  two  to  five  inches  long.  They 
have  no  bast  bundles,  and  the  stomata  are  abundant. 
The  indusium  is  narrow,  and  the  sporangium  spotted. 
In  diameter  the  megaspores  measure  from  400/^  to  550^ 
and  appear  **  as  if  sprinkled  with  minute  grains  of  white 
sugar."  They  may  be  distinguished  from  those  of 
typical  Isoetes  riparia  by  the  markings  being  slenderer 
and  shorter,  with  a  faint  resemblance  to  those  of  Isoetes 
eeJiinospora. 

At  present,  typical  plants  of  Isoetes  saeeJiarata  have 
been  found  only  on  tidal  flats  about  the  head  of  Chesa- 
peake Bay  and  the  rivers  that  empty  into  it.  A  com- 
plete list  of  the  stations,  with  a  map  and  discussion  of 
its  distribution,  was  published  in  the  Botanieal  Gazette 
for    September,     1903.       Two     seasonal     forms,     named 


THE  AMPHIBIOUS  QUILLWORTS.  241 

reticulata  and  Palnieri,  respectively,  have  been  found. 
It  is  a  remarkable  fact  that  Isoetes  riparia  forms  should 
be  found  only  at  the  head  of  Delaware  Bay,  and  Isoetes 
saccharata  forms  only  in  similar  situations  in  a  neighbour- 
ing bay,  especially  since  the  two  are  so  closely  related. 
It  would  seem  as  if  the  progeny  of  a  single  species 
settling  in  the  region  have  been  modified  by  the  sur- 
roundings until  they  have  assumed  their  present  forms. 
Mr.  Eaton  apparently  considers  that  Isoetes  saccharata  is 
represented  in  New  England,  since  he  has  recently 
described  the  variety  Ainesii  from  Massachusetts.  It 
appears,  however,  better  referred  to  Isoetes  Canadensis 
Robbinsii. 

Isoetes  Foveolata. 

Whatever  may  be  the  status  accorded  this  form,  at 
present,  it  is  certainly  closely  related  to  Isoetes  Engel- 
nianni.  The  patterns  of  the  markings  on  the  mega- 
spores  are  almost  identical,  but  there  is  so  much  differ- 
ence in  the  thickness  of  the  reticulations  that  the  spores 
present  a  very  different  appearance. 

Isoetes  foveolata  is  a  stouter,  shorter  plant  than  Isoetes 
Engehnanni,  with  from  fifteen  to  sixty  pinkish  leaves  two 
to    six    inches    long,    bearing    stomata 
mostly  near  the  tips.     The  peripheral 
bast  bundles  are  absent,  and  the  spo- 
rangia are    thickly  spotted  with    dark 
cells  which  are  often    assembled    into 
groups.     Some  plants  appear  to  bear 
only    megaspores.        These     are    from 
380/^  to  560/^  in  diameter,  flattened   on         /STw^L. 
the   hemisphere  bearing    the    commis- 
sures,   and    covered   with    reticulations   so  wide  and  so 


242  THE  AMPHIBIOUS  QUILLWORTS. 

numerous  as  to  almost  obliterate  the  openings  between 
them,  which  thus  resemble  little  pits.  This  appearance 
gives  the  plant  its  specific  name.  The  microspores  are 
dark  brown,  22/^  to  34/^  long,  and  marked  like  the  meg- 
aspores. 

Tsoetes  foveolata  pletiospora  is  a  larger  form,  with  longer 
and  more  numerous  leaves,  pinkish  in  colour.  The 
megaspores  are  similar  to  those  of  Isoetes  foveolata,  but 
with  higher,  thinner  crests,  especially  in  the  lower  part 
of  the  spore,  and  thus  have  a  great  resemblance  to  the 
spores  of  Isoctcs  Tuckermaiii.  Both  the  species  and 
variety  have  been  found  in  New  Hampshire  and  Massa- 
chusetts only,  and  there  in  but  few  stations. 

Isoetes    Gravesii. 

It  is  possible  that  geological  conditions  play  an  im- 
portant part  in  the  making  of  Isoctcs  species.  It  has 
been  noticed  that  a  very  slight  change  in  the  composi- 
tion of  the  soil  makes  a  change  in  the  species  inhabiting 
it.     A  close  student  of  the  genus  wrote  recently  : 

''  You  may  always  expect  to  find  certain  species  in 
certain  soils.  As  soon  as  I  see  a  pond  in  my  region  I 
can  usually  tell  what  species  of  Isoctcs  you  will  find  in  it 
if  they  occur  at  all." 

No  experiments  appear  to  have  been  made  to  dis- 
cover whether  the  same  species  will  take  on  different 
forms  when  grown  in  different  soils  ;  but,  should  this  be 
proved  to  be  true,  it  would  throw  much  light  upon  the 
relationship  of  Isoctcs  riparia  and  Isoctcs  saccharata,  and 
perhaps  give  a  clue  to  the  origin  of  the  plants  which 
have  been  named  Isoctcs  Gravesii.  Thus  far  they  liave 
been   found  in  only  a   few  stations  in   the  State  of  Con- 


THE  AMPHIBIOUS  QUILLWORTS.  243 

necticut.  When  first  discovered  they  were  referred  to 
Isoetes  Eatoni^  but  a  later  opinion  is  that  the  plants  are 
specifically  distinct.  In  the  shape  and 
size  of  the  spore  they  resemble  that 
species,  but  the  markings  are  more 
like  those  of  Isoetes  riparia.  As  in  Iso- 
etes  Eatoni   the   microspores  are  seldom        Mesasporeof 

Isoites  Gravesii. 

found. 

The  plants  have  from  fifty  to  seventy-five  leaves, 
which  are  erect  and  sharp-pointed,  and  possess  four  bast 
bundles.  The  indusium  is  narrow,  and  the  sporangium 
light  cinnamon  colour.  The  megaspores  are  from  350/^ 
to  400^  in  diameter,  greatly  flattened  in  the  upper  hemi- 
sphere, and  densely  covered  with  stout  truncate,  mostly 
single  columns.  The  shape  of  the  spores  is  very  charac- 
teristic. It  is  difficult  to  believe  that  a  species  of  this 
genus  should  be  restricted  to  so  small  a  region,  and  the 
idea  suggests  itself  that  this  is  still  another  form  of  the 
species  which  goes  under  the  name  of  Isoetes  Engelmanni 
valida  or  Isoetes  Eatoni.  The  author  would  be  inclined 
to  call  it  Isoetes  valida  Gravesii.  The  presence  of  the 
bast  bundles  in  the  leaves,  the  small  size  of  the  mega- 
spores, and  the  marked  flattening  they  display,  the  lack 
of  microspores,  and  the  dioecious  nature  of  the  plant,  all 
point  to  a  close  relationship  to  the  form  described  as 
Isoetes  Eatoni,  and  Mr.  Eaton  writes  that  if  this  plant  is 
ever  reduced  to  a  variety  it  must  be  made  a  variety 
of  this  form. 


Isoetes   Melanospora. 


This  peculiar  species  was  discovered  in  1869  by 
Canby,  who  found  it  growing  in  shallow  excavations  in 
granite  rock  on  Stone  Mountain,  Georgia.     It  is  remark- 


2u  THE  AMPHIBIOUS  QUILLWORTS. 

able  for  having  very  dark  grey,  almost  black,  mega- 
sporcs,  being  unique  in  this  respect  among  the  species  of 
eastern  America.  It  is  also  one  of  the  few  species  in 
which  the  indusium  completely  covers  the  sporangium. 
This  species  has  from  five  to  ten  tapering,  slender 
leaves  about  two  inches  long.  The  sporangia  are  rather 
roundish,  and  the  megaspores  are  from 
350/^  to  450"  in  diameter.  The  surface 
is  marked  by  many  slight  projections 
that  are  roundish  or  confluent,  form- 
ing low,  short,  scale-like  crests.  The 
microspores  are  smooth  or  slightly 
Megaspore  of  papillosc.     The  plant  has  been  found 

Isoetes  tnela7iospora.  .  1     1  1  •    •  1 

in  several  localities,  but  never  outside 
of  Georgia.  It  is  so  different  from  the  other  species  of 
the  East  that  identification  will  be  easy,  even  for  the 
beginner. 

Isoetes   Flaccida. 

The  only  species  of  quillwort  with  which  the  State  of 
Florida  is  credited  is  the  one  bearing  the  name  of  Isoetes 
flaccida.  In  general  appearance  it  is  like  all  the  am- 
phibious quillworts,  but  the'  spore-char- 
acters are  unlike  any  others  of  our 
region,  being  more  closely  related  to  vari- 
ous tropical  species.  This  difference,  and 
the  limited  area  it  inhabits,  make  it  an- 
other   species    easily    identified    by    the 

,         .  Meeaspore  of 

beginn  er.  isoetes  Jlacdda. 

The  leaves  are  from  ten  to  thirty-five  in  number,  and 
from  three  inches  to  two  feet  long.  The  plant  usually 
roots  beneath  the  water,  and  the  long  leaves  float  on  the 


THE  AMPHIBIOUS  QUILLWORTS.  245 

surface,  though  the  whole  phint  may  sometimes  be  found 
exposed.  The  sporangia  are  rather  small  and  are  com- 
pletely covered  by  the  indusium.  The  megaspores  are 
from  300/^  to  400 /"  in  diameter  and  are  marked  in  a  dis- 
tinct and  remarkable  way.  In  some  there  is  a  single 
lar^xe  button-like  tubercle  in  the  centre  of  each  of  the 
three  areas  outlined  by  the  commissures  and  equator;  in 
others,  there  are  several  smaller  tubercles  in  these  areas. 
On  the  lower  hemisphere  these  tubercles  incline  to  run 
together,  forming  thick  wrinkles.  The  equator  and  the 
commissures  are  unusually  heavy. 

Two  varieties  of  this  species  have  been  named.  The 
variety  rigida  is  smaller,  slenderer,  with  more  erect  leaves. 
The  variety  Cliapinani  is  distinguished  by  having  larger 
megaspores  that  are  almost  smooth  on  the  upper  hemi- 
sphere. Thus  far  Isoetes  flaccida  has  been  found  only 
in  Florida.  It  may  possibly  occur  in  the  southern  parts 
of  the  other  Gulf  States,  but  will  probably  always  be  a 
rare  species. 

Isoetes    Howelli. 

This  species  may  be  described  by  saying  that  it  is  like 
Isoetes  Nutt'allii,  with  the  exception  that  the  megaspores 
are  not  so  conspicuously  marked  with  roundish  warts, 
but  usually  have  low  crests  that  may  be  either  isolated 
or  confluent,  especially  in  the  lower  hemisphere.  The 
spores  are  practically  of  the  same  size,  often  dark  grey  or 
nearly  black,  and  the  author  is  inclined  to  regard  it  as  a 
form  of  Isoetes  Nuttallii  in  spite  of  the  differences  in 
habitat. 

The  species  has  a  larger  number  of  leaves  than  Isoetes 
Nuttallii,  which  is  to  be  expected  from  its  location  under 


246 


THE  AMPHIBIOUS  QUILLWORTS. 


water,  but  it  is  significant  that  the  peripheral  bast  bun- 
dles,prominent  in  Isoetes  Niittallii  are  also  present,  while 
the  numerous  stomata  found  indicate  that  it,  too,  is 
often  exposed  to  the  air.  It  is  found 
only  within  the  range  of  its  relative 
— from  California  to  Idaho  and  Wash- 
ington. Two  other  forms,  described 
as  Isoetes  Underzvoodii  and  Isoetes  nil  da, 
are  now  believed  to  be  the  same  as 
Isoetes  Howe  Hi.  Mr.  Eaton  has  re- 
cently described  a  plant  from  the  same 
range  which  he  calls  Isoetes  Piperi.  It  is  distinguished 
by  heavier  markings  on  the  megaspores  and  would  seem 
to  be  still  another  variety. 


Meg^aspore  of 
Isoetes  Hoivelli, 


THE  TERRESTRIAL  QUILLWORTS 


THE  TERRESTRIAL  QUILLWORTS, 


T  is  singular  that  while  the 
quillworts  of  eastern  Amer- 
ica are  mostly  characterised 
by  megaspores  marked  with 
spines  and  crests,  those  of 
the  West,  especially  in  the 
warmer  parts,  are  marked 
with  fine  dots  and  warts. 
This  apparent  influence  of 
temperature  on  the  mark- 
ings of  the  spores  is  also 
observed  in  the  Southeast, 
where  the  spines  and  crests 
fade  into  tubercles.  Along 
with  these  peculiar  patterns 
of  spore-markings  in  the  West  goes  a  tendency  of  the 
plants  to  grow  out  of  water,  and  in  that  region  there  are 
several  species  that  are  by  courtesy  called  terrestrial. 
That  they  are  terrestrial  in  the  sense  that  a  lily  or  a 
dandelion  is  terrestrial  is  of  course  incorrect.  Many  of 
these  species  are  covered  with  water  for  a  part  of  the 
year  at  least,  and  the  whole  genus  is  so  fully  committed 
to  a  watery  habitat  that  they  always  grow  in  moist  places. 
When,  for  any  reason,  the  places  in  which  they  grow 
become  dry,  the  plants  go  into  a  state  of  aestivation  in 
which  the  leaves  disappear  and  the  whole  plant  assumes 


2SO  THE  TERRESTRIAL  QUILLWORTS. 

a  resting  condition.  The  spores  of  all  are  very  much 
alike  and  show  a  regular  gradation  from  one  extreme 
to  the  other.     Evidently  all  the  species  are  closely  related. 

Isoetes    Melanopoda. 

One  of  the  best-known  of  the  terrestrial  species  is 
Isoetes  Melanopoda,  which  was  first  discovered  in  Illinois 
and  appears  to  be  peculiar  to  the  prairie  region  extend- 
ing from  that  State  southwestward.  It  is  often  found  in 
alkaline  flats,  and  its  behaviour  there  is  described  as 
follows : 

"  Many  of  the  wells  and  springs  running  into  or  passing  through  this 
clay  are  damaged  or  sometimes  rendered  unfit  for  use  by  the  quanti- 
ties of  sulphates  of  magnesia  and  soda  entering  into  solution  there 
from.  Occasionally  this  clay  rises  to  the  surface,  forming  low  level 
places  which  are  popularly  known  as  alkaline  flats.  During  winter 
and  spring,  while  the  rainy  weather  lasts,  the  flats,  owing  to  their 
level  surface  and  imperfect  drainage,  are  very  wet,  but  by  or  before 
the  first  of  July,  when  the  dry  summer  has  well  begun,  they  have  be- 
come the  driest  of  all  dry  places,  for  the  clay  prevented  the  water  from 
soaking  in,  and  the  soil  is  so  thin  that  an  adequate  store  of  moisture 
could  not  be  laid  up.  These  flats  are  the  home  of  Isoetes  Butleri. 
There  are  occasional  basins  in  the  flats  which  contain  more  or  less 
water,  and  here  Isoetes  melanopoda  grows.  It  also  occurs  in  nearly 
all  ponds,  ditches,  and  wet-weather  streams.  It  is  more  common 
than  the  other,  or  at  least  it  appears  so,  and  it  is  so  much  easier  to 
find,  owing  to  its  greater  size  and  paucity  of  companions.  It  disap- 
pears in  August." 

From  this  it  will  be  seen  that  this  plant  is  scarcely  a  dry- 
ground  species,  though  Underwood  so  lists  it.  Baker 
places  it  among'  the  amphibious  species.  It  is  found  in 
damp  sands,  however,  and  has  been  collected  in  a  water- 
melon   patch.     A  certain  amount  of  dryness  seems  ac- 


THE  TERRESTRIAL  QUILLWORTS. 


251 


ceptable  to  it,  at  least  so  far  as  the  production  of  fruit 
is  concerned,  for  it  has  been  found  that,  when  covered 
with  water,  the  leaves  last  through  the  season,  though 
spores  are  seldom  produced. 

The  leaves  of  this  species  are  from  fifteen  to  sixty  in 
number,  slender,  erect,  and  from  six  inches  to  a  foot 
long.  They  are  usually  black  and  shining  at  base;  hence 
the  specific  name.  As  in  all  the  species  that  are  exposed 
for  a  considerable  time  to  the  air,  the  leaves  possess 
stout  peripheral  bast  bundles  which 
aid  in  holding  them  erect.  The  indu- 
sium  is  very  narrow  or  sometimes  ab- 
sent, and  the  sporangium  is  spotted. 
The  megaspores  are  usually  small,  but 
vary  in  size,  averaging  from  250/"  to 
40O/"  in  diameter.  They  have  broad, 
low  commissures  and  are  marked  with 
indistinct  dots  and  low  vermiform  wrinkles.  Except  for 
the  fact  that  they  are  not  dark  coloured,  they  have  a 
close  resemblance  to  those  of  Isoetes  inelanospora.  The 
microspores  are  spinulose.  The  megaspores  and  micro- 
spores are  usually  borne  on  separate  plants. 

As  the  water  in  its  habitat  disappears,  the  leaves  be- 
gin to  shrivel,  and  soon  little  holes  are  left  in  the  soil 
at  the  bottom  of  which  are  the  bulbs  and  sporangia. 
With  the  renewal  of  moisture  the  spores  and  the  parts 
surrounding  them  rise  and  float  away,  to  form  new  colo- 
nies. This  species  is  found  from  Illinois,  Iowa,  and  Ne- 
braska to  Texas,  and  it  also  has  a  variety  in  California 
which  differs  in  having  smooth  megaspores  and  larger 
microspores.  In  some  parts  of  its  range,  Isoetes  melano- 
poda  is  abundant,  but  it  is  not  evenly  distributed,  being 
often  rare  or  absent.     In    Tcx4S  a  larger  plant  with  pale 


Megaspore  of 
Isoetes  melatiopoda. 


252  THE  TERRESTRIAL  QUILLWORTS. 

leaf  bases  and  a  broader  indusium  is  called  the  variety 
pallida, 

Isoetes  Butleri, 

Closely  related  to  Isoetes  nielanopoda  by  spore  charac- 
ters, at  least,  is  the  species  called  Isoetes  Butleri,  which 
is  able  to  grow  in  even  drier  localities,  and  closely 
approaches  our  idea  of  a  terrestrial  species.  The  effect 
of  the  lack  of  moisture  is  doubtless  shown  by  the  fact 
that  it  is  a  smaller  plant  with  shorter  and  fewer  leaves. 
It  shows  its  dependence  upon  water,  however,  by 
disappearing  earlier  in  the  year  than  Isoetes  nielanopoda, 
often,  in  the  South,  before  the  first  of  July. 

In  this  species  the  sexes  seem  always  to  be  separate. 
The  megaspores  are  larger  than  those 
of  Isoetes  inelanopoda,  measuring  from 
400 /"  to  600 /"  in  diameter,  and  marked 
with  heavier  warts  or  points;  otherwise 
they  are  quite  like  them.  Isoetes  Biit- 
leri  has  been  reported  from  Missouri, 
Megasporeof  Oklahoma,    and  Tennessee,  and    is  as 

Isoetes  B utter i.  .  t        1         1      1 

yet  a  rare  species.  It  doubtless  occurs 
at  many  other  points.  The  variety  innnacidata  is  larger, 
with  unspotted  sporangia. 

Isoetes  Nuttallii. 

Isoetes  Nuttallii  is  a  species  of  the  Northwest,  first 
found  along  the  Columbia  River,  in  Oregon,  by  the 
botanist  whose  name  it  bears.  It  is  usually  about  three 
inches  in  height,  with  firm,  erect  leaves  from  twenty  to 
sixty  in  number.  It  grows  in  wet  places,  but  apparently 
never  under  water.  The  sporangia  are  entirely  covered 
by  the  indusium,  and  the  megaspores  are  usually  quite 


THE  TERRESTRIAL  QUILLWORTS.  253 

small  —  from  250."  to  500/^  in  diameter.  The  megaspores 
are  very  characteristic,  being  wliite  or  light  grey  in 
colour,  with  a  peculiar  glassy  lustre,  as 
though  made  of  porcelain.  They  are 
marked  by  small,  regular  warts,  which  are 
sometimes  so  minute  as  to  be  barely 
distinguishable.  They  have  the  greatest 
resemblance  to  the  spores  of  Isoctes  Bo- 
landcri,  and  the  two  might  be  regarded  /J^e^es^NuJ^a//'i/. 
as  forms  of  a  single  species,  one  growing  beneath  the 
water  and  the  other  modified  for  an  aerial  existence. 
The  two  are  found  in  the  same  general  region,  hoctcs 
Nuttallii  being  reported  from  California  to  British  Co- 
lumbia and  Idaho. 

Isoetes    Orcutti. 

The  plants  referred  to  hoctcs  Orcutti  belong  to  the 
same  general  group  of  which  hoctcs  Nuttallii  may  be 
taken  as  the  type.  The  megaspores,  however,  are  very 
smooth,  at  best  having  only  a  faint  granular  appearance. 
They  have  the  same  glassy  lustre  as  those  of  hoctes 
Nuttallii  and  are  dark  blue-grey  in  colour.  The  indu- 
sium  is  entire.  From  resemblances  of  the  spores, 
indusium,  and  habitat,  the  author  has  no  doubt  that  this 
isasouthern  formof  hoctcs  Nuttallii,  and 
believes  it  would  be  better  characterised 
by  calling  it  hoctcs  Nuttallii  Orcutti. 

The  leaves  of  this   form  are  few,  from 

two     to    four    inches    long,    and    contain 

from   two     to    four    bast    bundles.     The 

Megasporeof       Hicgasporcs  are  from  240."  to  300/^  in  di- 

Jsoetes  Orcutti.  i         i  •  11 

ameter,  and    the    microspores    are   dark 


254  THE  TERRESTRIAL  QUILLWORTS. 

brown,  22/^  to  35/^  long.  This  form  was  found  in  the 
vicinity  of  San  Diego,  California,  and  has  since  been  dis- 
covered in  Lower  California.  It  grows  in  the  evanescent 
pools  mentioned  as  the  habitat  of  Pilularia  Americana^ 
and,  like  that  plant,  it  disappears  soon  after  the  pools 
dry  up.  When,  through  lack  of  winter  rains,  the  pools 
do  not  appear,  the  plants  remain  dormant  sometimes  for 
two  years  or  more  in  succession. 

Isoetes  Minima. 

This  diminutive  species,  with  leaves  from  one  to  two 
inches  long,  was  collected  by  Suksdorf  on  a  damp  prairie 
near  Waverly,    Washington,  and  has  not  been  found  else- 
where.    The    leaves   have  the  bast  bun- 
dles usual  to  terrestrial  species,  and  the 
indusium    nearly    covers    the    unspotted 
sporangia.      The    megaspores    are     from 
290/^  to  350/"  in  diameter,  covered   with 
short,    blunt,  slender  spinules  that  in  ar- 
rangement   suggest    what  would    result    if         Megasporeof 

Isoetes  viiniina. 

the  warts  on  the  spores  of  other  species 
common    to  the   same    general  region    were    elongated. 
The  equator    is    also  set  with  these   points,    making   it 
"  resemble  a  ship's   wheel."     This  is,  so  far  as  known, 
the  smallest  American  species. 


CHECKLIST  OF  THE  FERN  ALLIES 


CHECKLIST   OF   THE   SPECIES   AND  PRIN- 

CIPAL  VARIETIES  OF  FERN  ALLIES  IN 

NORTH  AMERICA,  NORTH  OF 

MEXICO, 

AZOLLA. 

Azolla  Carolinianuni  Willd. 
Azolla  filiculoides  Lam. 

EQUISETUM. 
Eqiiisetum  arvense  L. 
Eqnisetum  arvense  f,  cain2)€sfre  Schultz 
Kqaisetum  arvense  f.  decfunbens  Meyer 
Eqiiisetiun  arvense  f.  dijf'tfstun  A.  A.  Eaton 
Eqnisetum  arvense  f,  2^f^^ttdosilvaticinn  Milde 
Equisetiun  Ferrissi  Clute 
Eqiiisetum  ffnviatile  L. 
Equiseturn  flaviatile  f.  lifnosuni  (L.) 
Eqiiisetum  Funstoni  A.  A.  Eaton 
Equiseturn  hiemale  L. 

Equiseturn  hiemale  intermedium  A.  A.  Eaton 
Equisetum  Jiiemale  robustum  (A.  Br.) 

Equiseturn  robicstinn  A.  Br. 
Equisetum  Iwvigatum.  A.  Br. 
Equisetum  litorale  Kuhl. 
Equisetum  palustre  L. 
Equisetum  pratense  Ehrh. 
Equisetum  scirpoides  Michx. 
Equisetum  silvaticum  L. 
Equisetum  telmateia  Ehrh. 
Equisetum  variegatum  Schleich. 
Equisetum  variegatum  Alask<inuni  A.  A.  Eaton 


258  CHECKLIST    OF    THE    FERN    ALLIES. 

ISOETES. 

Isoetes  Bolandevi  Engelm. 

Isoetes  Solanderi  pygmaea  (Engelm.) 

Isoetes  pygmaea  Engelm. 
Isoetes  Bolanderi  Somiei  Renders. 
Isoetes  Butleri  Engelm. 
Isoetes  Batleri  f,  itnmaculata  Engelm. 
Isoetes  Canadensis  (Engelm.) 

Isoetes  Dodgei  A.  A.  Eaton 
Isoetes  Canadensis  Mobinsii  A.  A.  Eaton 

Isoetes  saccharata  Amesii  A.  A.  Eaton 
Isoetes  echinospora  liraunii  (Dm.) 
Isoetes  echinospora  Braunii  /.  Boottii  (A.  Br.) 
Isoetes  echinospora  Braiinii  f.  robusta  (Engelm.) 
Isoetes  echinospora  Flettii  A.  A.  Eaton 
Isoetes  echinos2>ora  inarititna  (Undervv.) 

Isoetes  mar  it  i in  a  Undervv. 
Isoetes  echinospora  niuricata  (Dur.) 
Isoetes  Engelnianni   A.  Br. 
Isoetes  Engelinanni  Caroliniana  A.  A.  Eaton 
Isoetes  Engelnianni  /.  fontana  (A.  A.  Eaton) 

Isoetes  E7igelmanni  fo7itatia  A.  A.  Eaton 
Isoetes  Engelnianni  f,  Georgiana  Engelm. 
Isoetes  flaccida  Shuttlvv. 
Isoetes  flaccida  f,  Chapinani  Engelm. 
Isoetes  flaccida  f,  rigida  Engelm, 
Isoetes  foreolata  A.  A.  Eaton 
Isoetes  foveolata  jdenospora  A.  A.  Eaton 
Isoetes  Gravesii  A.  A.  Eaton 
Isoetes  hieroglyithica  A.  A.  Eaton 
Isoetes  Howellii  Engelm. 

Isoetes  nuda  Engelm. 

Isoetes  Underwoodii  Renders, 
Isoetes  Howellii  Piperi  (A.  A.  Eaton.) 

Isoetes  Piperi  A.  A.  Eaton. 
Isoetes  lacustris  L, 
Isoetes  lacustris  2>aiipercala  Engelm. 

Isoetes patcpercula  A.  A.  Eaton 

Isoetes  occidenialis  Renders. 


26o  CHECKLIST    OF    THE    FERN    ALLIES. 

Isoefes  Macotiiiii  A,  A.  Eaton 

Isoetes  iu(ici'€>spora  Diir. 

Isoetes  melanopoda  J.  Gay 

Isoetes  meliinopodft  f,  pallida  Engelm. 

Isoetes  melanopoda  f,  Califot'tiiea  A.  A.  Eaton 

Isoetes  inelaiiospora  Engelni. 

Isoetes  minima  A.  A.  Eaton 

Isoetes  Nuttallii  A.  Br. 

Isoefes  Suksdorfz'i  Baker 
Isoetes  Orcattl  A.  A.  Eaton 
Isoetes  riparia  Engelm. 
Isoetes  saceharata  Engelm. 
Isoetes  saceharata  /.  I*almeri  A.  A.  Eaton 
Isoetes  saceharata  f,  reticulata  A.  A.  Eaton 
Isoetes  Tucker numi  A.  Br. 
Isoetes  I'uckermatii  Harreyi  (A.  A.  Eaton) 

Isoetes  Harveyi  A.  A.  Eaton 
Isoetes  Tnckennani  heterospora  (A.  A.  Eaton) 

Isoetes  heterospora  A.  A.  Eaton 
Isoetes  Tucker mani  /.  horealis  A.  A.  Eaton 
Isoetes  truncata  (A.  A.  Eaton) 
Isoetes  echinospora  trimcata  A.  A.  Eaton 
Isoetes  valida  (Engelm) 

Isoetes  Engelman7ii  valida  Engelm. 

Isoetes  Eatoni  Dodge 

LYCOPODIUM. 

Lycopodiuin  alopecaroldes  L, 

Lycopoiliam  alopecaroldes  adpressuni  Chapm. 

Lycopodium  adpressum  (Chapm.) 

lycopodittm  Chapmaiuii  Underw. 
Lycopodlam  alopecnroidesf,  piiinatum  Chapm. 

lycopodium  piniiatiDti  (Chapm.) 
Lycopodium  alpinum  L. 
Lycopodium  atinotinum  L. 
Lycopodium,  annotiuani  jmngens  Spring, 
Lycopodium  Caroliuietinim  L. 
Lycopodium  ceruuum  L. 


262  CHECKLIST    OF    THE    FERN    ALLIES. 

Lycopodiani  clavatuni  L. 

Lycojtodiuni  clavatuni  /.  rnonostachyoti  Hook. 

Lycopodiuni  coniplanatum  L. 

Lycopodiuni  coniplauatutti  rJtainwcyparissus  (A.  Br.) 

Lycopodium  chamcEcyparissus  A.  Br. 

Lycopodium  tristachyon  Pursh. 
LiycopodiiuH  coniplanatum  f,  flahelli forme  Fernald 
Lycopodhini  coniplanatuni  /.  Wibhei  Haberer 
Lycopodinni  lucidtiluni  Michx. 
Lycopodium  lucidtilum  2}orophylum  (Lloyd  &Underw.) 

Lycopodium  porophyhun  Lloyd  &  Under w. 
Lycopodium  lucitlidum  f.  occidentale  Clute 
Lycopodium  inundatum  L. 
Lycojjodiuiu  inundatum  f.  Sigelovii  Tuckerm. 
Lycopodium  obscurum  L. 

Lycopodiuni  dendroideum  Michx 
Lycopodium  sahincefolium  Willd. 
Lycopodium  selago  L. 
Lycopodium  Sitchense  Rupr. 

MARSILIA. 

Marsilia  quadrifolia  L. 
Mfirsilia  macropoda  Engelm. 
Marsilia  uucinata  A.  Br. 
Marsilia  vestita  H.  «&  G. 

PILULARIA. 
Pilularia  Americana  A.  Br. 

PSILOTUM. 

Psilotum  triquetrum  S\v. 
Psilotuvi  nudum  (L.) 

SELAGINELLA. 

Selaginella  apus  Spring, 
Selaf/inella  arenicola  Underw. 
Selaginella  arenaria  Underw. 
Selaginella  Higelovii  Underw. 


264  CHECKLIST    OF    THE    FERN    ALLIES. 

SelagineUa  cinerascens  A.  A.  Eaton 

Selaginella  bryoides  (Nutt.) 
SelagineUa  JJouglasii  (H.  &  G.) 
Selaginella  lepidophylla  Spring. 
Selaginella  Ludoviciana  A.  Br. 
SelagineUa  Oregana  D.  C.  Eaton 

Selaginella  striithioloides  (Presl) 
Selaginella  Pringlei  Baker 
Selaginella  rupesU'is  (L.) 
SelagineUa  rupestris  Sherivoodii  (Underw.) 

Selaginella  Sherivoodii  (Underw.) 
Selaginella  rupestris  Fendleri  Underw. 
Selaginella  rupestris  acanthonofa  (Underw.) 

Selaginella  acanthonola  (Underw.) 
SelagineUa  rupestris  torfijHla  (A.  Br.) 

Selaginella  toriipila  A,  Br. . 
Selaginella  rupestris  rupincola  (Underw.) 

Selaginella  rti^inrola  Underw. 
Selaginella  rupestris  flensa  (Rydb.) 

Selaginella  densa  Rydb. 
Selaginella  spinosa  Beauv. 

Selaginella  selaginoides  (L.) 
Selaginella  Watsoni  Underw, 
Selaginella  Watsoni  jnittica  (U.  C.  Eaton) 

Selaginella  mutica  D.  C.  Eaton 

SALVINIA. 
Salvinia  natans  Hoffm. 


EXCLUDED  SPECIES. 

JPlquisetuni  Mexicanuni  Milde 
Equisetuni  ramosissimuni  Desv. 
Marsilia  fenuifolia  Enoelm. 
Selaginella  jnlifera  A.  Br. 


266 


CHECKLIST    OF    THE    FERN    ALLIES. 


Authors'  Names   Abbreviated  in  the  Checklist  of  Fern 

Allies. 


A.  Br.     A.  Braun. 
Beauv.     P.  de  Beauvois. 
Chapm.     A.  W.  Chapman. 
Desf.     R.  L.  Desfontaines. 
Dur.     Durieu, 
Ehrh.     F.  Ehrhart. 
Engelm.     G.  Engelmann. 
H.  &  G.     Hooker  &  Greville. 
Renders.     L.  F.  Henderson. 
Hoffm.     G.  F.  Hoffman. 
Hook.     W.  J.  Hooker. 

Willd.     K. 


Kuhl.     Kuhlewein. 
L.     Linnaeus. 
Lam.     J,  B.  de  Lamarck. 
Michx.     A.  Michaux. 
Nutt.     Thomas  Nuttall. 
Rupr.     Ruprecht. 
Rydb.     P.  A.  Rydberg. 
Schleich.     Schleicher. 
Sw.     O.  Swartz. 
Tuckerm.     E.  Tuckerman. 
Underw.     L.  M.    Underwood. 
Willdenow. 


GLOSSARY. 

Aculeate. — Armed  with  prickles. 
Acuminate.— Tapering  to  a  slender  point. 
Acute. — Pointed  ;  ending  in  a  sharp  point. 

Adventitious. — That  which  comes  from  abroad  ;  as  a  plant  intro- 
duced by  chance. 
Adventitious  Buds. — Buds  produced  without  order  on  any  part 

of  the  plant. 
Amphibious. — Said  of  plants  that  are  covered  with  water  for  a  part 

of  each  year. 
Anastomosing. — Forming  a  network  ;    as  veins  uniting  with  one 

another. 
Androspore. — The  smaller  spore  in  Isoetes  and  various  other  fern 

allies ;  a  microspore. 
Annulus. — A  ring,  especially  that  which  surrounds  the  spore-cases 

in  most  ferns. 
Antheridia. — The  male  organs  on  the  prothallium. 
Apiculate. — Terminating  abruptly  with  a  small  point. 
Appressed.  —  Turned  upward  against  the  stem  ;  said  of  small  leaves. 
ArcheGONIA. — The  female  organs  on  the  prothallium. 
Areola  (Pl.  Areola). — A  space  enclosed  by  anastomosing  veinlets- 
Areolate. — Having  areolae. 

Articulated. — Jointed  or  having  the  appearance  of  a  joint. 
AURICLED.— Eared. 

Auriculate. — With  ear-like  appendages. 
Bast, — Strands  of  strengthening  tissue. 
BiPiNNATE. — Twice  pinnate. 
Bipinnati FID. —Twice  pinnatifid. 
Blade. — The  expanded,  leafy  portion  of  a  frond. 
Bristle. — A  stiff  hair ;  any  slender  outgrowth  from  the  plant,  as  in 

the  fruiting  parts  of  filmy  ferns. 
Bulbiferous. --Bearing  little  bulblets. 


268  GLOSSARY. 

BULBLET. — A  small  bulb,  especially  such  as  are  borne  upon  leaves  or 
in  their  axils. 

Carina  (Pl.   Carina). — A   small   ridge,  especially  the  ridges   on 
the  stems  of  Equiseiiun. 

Catkin. — A  name  given  to.  the  fruiting  parts  of  many  fern  allies. 

Caudate. — With  a  slender,  tail-like  appendage. 

Caudex. — A  trunk,  especially  that  of  a  tree-fern. 

Chaff. — Slender,  papery  scales. 

Chartaceous. — Having  the  texture  of  parchment. 

Chlorophyll, — The  green  colouring  matter  of  plants. 

Ciliate. — Fringed  with  fine  hairs. 

Circinate. — Coiled,  as  the  buds  of  ferns,  from  tip  to  base. 

Clay  ATE.— Club-shaped. 

Compound. — Divided  into  two  or  more  portions  ;   said  of  the  frond. 

Conceptacle. — The  structure  that  encloses  the  sori  in  certain  fern 
allies ;  a  sporocarp. 

Cone. — A  name  applied  to  the  fruiting  parts  of  Eqidsetum. 

Confluent. — Blended  together. 

Cordate. — Heart-shaped  ;  ovate  with  a  sinus  at  base. 

Coriaceous.— Like  leather  in  texture. 

Crenate. — With  rounded  teeth  ;  said  of  margins. 

Crenulate. — Scalloped  with  small  rounded  teeth. 

Crosier. — An  uncoiling  frond. 

Crown. — The  growing  end  of  the  rootstock  or  caudex. 

Cuneate. — Wedge-shaped. 

Cuspidate. — Terminating  in  a  sharp,  hard  point. 

Deciduous. — Not  evergreen  ;  subject  to  being  shed  at  certain  sea- 
sons. 

Decompound. — Several  times  compounded  or  divided. 

Decumbent. — Not  erect ;  bending  along  the  ground. 

Decurrent. — Extended  downward  along   the  rachis ;  said  of  the 
bases  of  pinnas,  etc. 

Deflexed. — Bent  abruptly  downward. 

Dentate. — Toothed  ;  said  of  the  margins. 

Denticulate.— Finely  toothed. 

Depauperate. — Starved  ;  prevented  from  coming  to  its  natural  size 

through  lack  of  nourishment. 
DiCHOTOMOUS. — Forked  in  pairs  ;  two-forked. 


GLOSSARY.  269 

Dimidiate.— Halved,  or  as  if  one  half  were  wanting,  as  in  the  pinnules 

of  some  adiantums. 
Dimorphous, — Of  two  forms ;  said  of  ferns  whose  fertile  and  sterile 

fronds  are  not  alike. 
Dissected. — Cut  into  many  lobes  or  divisions. 

DORSI-VENTRAL.— Having  an  evident  upper  and  under  surface  ;  flat- 
tened in  a  plane  parallel  with  the  earth. 
Elater. — One  of  the  two  bands  into  which  the  outer  coat  of  the 

Eqiiisetiun  spore  splits  at  maturity. 
Elliptical. — Oblong  with  rounded  ends. 
Emarginate. — Notched  at  the  summit. 
Entire. — Not  divided  ;  said  of  fronds  or  pinnules  whose  margins  are 

without  notches  or  teeth. 
Falcate. — Scythe-shaped  ;  curved  upward. 
Fertile. — Producing  spores. 
FiBRO-VASCULAR. — Consisting  of  wood-fibres  and  ducts,  as  in   the 

stems  of  the  fernworts. 
Filiform. — Thread-like. 
Flabellate. — Fan-shaped. 
FovEOLATE.— Honeycombed. 
Frond. — A  fern  leaf.     Properly  the  word  frond  includes  both  stipe 

and  blade,    but  frequently  it   is  used    simply  to  designate  the 

leafy  portion. 
Fruit. — Sporangia. 
Fruit-dot. — A  sorus. 
Fugacious.— Short-lived  ;  falling  early. 
Glabrous, — Smooth. 
Gland. — A  minute   globular  or   pear-shaped   organ   which  usually 

secretes  a  resinous,  waxy,  gummy,  or  aromatic  product. 
Glandular. — Furnished  with  glands. 
Glaucous. — Covered  with  a  very  fine  powdery  substance,  as  plums, 

are. 
Glutinous. — Covered  with  a  sticky  exudation. 
Gynospore. — The   larger  spore  in   Isoctcs  and   other  fernworts;  a 

megaspore. 
Habit. — The  general  appearance  of  a  plant. 
Habitat. — The  natural  dwelling-place  of  an  animal  or  plant. 
Heterosporous. — Producing  spores  of  two  sizes  or  kinds. 


270  GLOSSARY. 

Hirsute. — Having  coarse  stiff  hairs. 

liMBRlCATED. — Overlapping  or  breaking  joints,  like  shingles  on  a  roof. 

Incised. — Cut  into  deep,  sharp  teeth. 

INDUSIUM  (PL.  INDUSIA).— The  thin,  scale-like  covering  of  immature 

sori. 
Internode. — The  spaces  between  the  nodes  of  the  stem,  especially 

in  Equi'selKm. 
Involucre. — The   cup-shaped   process   surrounding   the   sporangia 

in  the  filmy  ferns  ;  an  indusium. 
Isosporous. — Producing  spores  of  one  kind. 
Laciniate. — Cut  into  deep,  narrow,  irregular  lobes  ;  slashed. 
Lanceolate.  —  Rather  narrow  and  tapering  to  the  apex  ;  occasion- 
ally tapering  at  base  also. 
Lampna. — A  blade  ;  the  leafy  portion  of  a  frond. 
Leptosporangiate. — Producing    sporangia    from    the    superficial 

tissues  of  the  frond. 
Ligule. — A   small   triangular   tongue-like  organ   on   the  leaves   of 

Isoetes. 
Linear.  —  Long  and  narrow. 
Lobe, — One  of  the  small  divisions  of  a  frond. 
Lunate. — Shaped  like  a  half-moon. 
Macrosp.ORE.  — A  megaspore. 
Marginal. — Situated  on,  or  close  to,  the  margin. 
Megaspore. — The  larger  spore  in  those  species  having  two  sizes  of 

spores,  especially  in  Isoetes. 
Membranaceous. — Like  a  membrane  ;  very  thin  and  flexible. 
Microspore. — The  smaller  spore  in  those  species  with  spores  of  two 

sizes,  especially  in  Isoetes, 
Midrib. — The  prolongation  of  the  stipe  through  an  undivided  frond 

or  pinna. 
Midvein. — The  principal  vein  in  a  pinnule  or  segment. 
Mucronate. — Having  the  midvein   prolonged  beyond   the  pinnule, 

forming  a  point. 
Node. — The  swollen  regions  of  a  stem  from  which  the  leaves  grow, 

especially  in  Equisetum. 
Oblanceolate.— The   reverse   of    lanceolate  ;    broadest   near   the 

apex. 
Oblong.— Two  or  three  times  longer  than  broad. 


GLOSSARY.  271 

Obovate. — The  reverse  of  ovate. 

OirruSE. — Blunt;  without  point. 

Orbicular.— Circular. 

Ovate. — Egg-shaped  ;  the  broadest  part  near  the  base. 

Paleaceous. — Clothed  with  chaff. 

Palmate. — With  spreading  divisions,  like  the  fingers  of  the  hand. 

Panicle. — A  cluster  of  fruit  in  which  the  stems  branch  more  or  less. 

Papyraceous,— Paper-like. 

Pedicel. — A  tiny  stalk  ;  especially  the  stalk  of  the  sporangium. 

Peduncle. — A  stalk  ;  especially  the  stalk  of  the  fruiting  parts  in 

Lycopodhim . 
Peltate. — Shield-shaped  ;    said    of    scales    and    indusia    that   are 

attached  to  the  frond  by  their  centres. 
Persistent. — Not  falling  away  ;  remaining  on  the  plant. 
Petiole. — Same  as  stalk  and  stipe. 

Pinna  (Pl.  Pinn^). — One  of  the  primary  divisions  of  a  frond. 
Pinnate. — Consisting  of  several  leaflets  arranged  on  each  side  of  a 

common  petiole  or  rachis. 
PiNNATiFlD. — Divided  in  a  pinnate  manner,   but  with   leaflets  not 

entirely  separate. 
Pinnule. — One  of  the  small  divisions  of  a  pinnate  leaf. 
Procumbent.— Lying  along  the  ground. 
Proliferous. — Giving  rise  to  new  plants. 
Prothallium  (Pl.  Prothallia). — The  minute  scale-like  growth 

from  the  spore  of  a  fern  wort. 
Pubescence.— A  covering  of  soft,  short  hairs. 
Pubescent.— Covered  with  fine,  soft  hairs. 
Quadripinnate.— Four  times  pinnate. 

Rachis. — The  continuation  of  the  stipe  through  a  compound  frond. 
Receptacle. — The   part  of  the  frond  to  which  the  sporangia  are 

attached,  especially  in  the  filmy  ferns. 
Reflexed. — Abruptly  bent  downward  or  backward. 
Reniform.— Kidney-shaped. 

Revolute. — Rolled  backward,  as  the  margins  of  some  fronds. 
Rhizome. — An  underground  stem  ;  a  rootstock. 
RooTSTOCK, — Same   as   rhizome.     The   portion    that  produces    the 

fronds  or  stems  in  most  of  our  species. 
Scales. — The  chaff  on  the  stems  of  ferns. 


272  GLOSSARY. 

SCANDENT.— Climbing. 

Segment. — One  of  the  smaller  divisions  of  a  pinnatifid  frond. 

Serrate. — With  saw-like  teeth  ;  said  of  margins. 

Sessile.— Without  a  stalk. 

Sheath. — The  circle  of  confluent  leaves  in  Eqicisehtm. 

Sinuate. — Wavy  ;  said  of  margins. 

Sinus. — The  re-entering  space  between  two  lobes. 

SORUS  (PL.  SORl). — An  assemblage  of  sporangia  ;  a  fruit  dot. 

Spatulate.— Spoon-shaped. 

Spike. — A  name  given  to  the  fruiting  parts  of  the  fern  allies. 

Spine. — A  sharp  point ;  a  thorn. 

Spinulose. — Thorny;  set  with  small  spines. 

Sporangium  (Pl.  Sporangia.)— A  tiny  globe  in  which  the  spores 

are  produced. 
Spore. — A  one-celled  body,  the  fruit  of  the  higher  cryptogams  ;  it  is 

produced  asexually  and  is  the  analogue  of  a  seed. 
Spore-case. — Same  as  sporangium;   the  case  in  which  the  spores 

are  borne. 
Sporocarp. — A  capsule-like  structure  enclosing  the  sori  in  certain 

fern  allies,  as  in  Marsilia. 
Sporophyll. — A  leaf  that  bears  spores,  often  modified  for  the  pur- 
pose. 
Stalk. — Same  as  stipe. 
Sterile. — Barren.     Said   of  leaves   or  stems  that  do  not  produce 

spores. 
Stipe. — The  petiole  or  stalk  of  the  fern  leaf  which  bears  the  leafy 

portion  aloft. 
Stolon.  —A  trailing,  or  often  underground,  branch. 
Stomata. — Minute  openings  in  the  leaves  of  plants. 
Subulate. — Awl-shaped. 
Ternate. — With  three  nearly  equal  divisions. 
Tomentose. — Covered  with  matted  wool. 
Tomentum. — Close  matted  woolly  hairs. 
Tooth. — The  smallest  division   of  a  frond  ;  a  slender  prolongation 

from  the  sheath  in  Equisettiin. 
Tortuous.— Bent  or  twisted  in  different  directions. 
Tri pinnate. — Three  times  pinnate. 
Truncate.— Appearing  as  if  cut  off  abruptly. 


GLOSSARY.  273 

Undulate. — Wavy-margined. 

Vallecula  (Pl.  Vallecul/e). — A  hollow;  especially  the  grooves 

in  the  stem  of  Equisetum. 
Vallecular. --Pertaining  to  the  vallecula. 

Vascular. —Containing  vessels,  ducts,  etc.,  as  the  stems  of  ferns. 
Vein.— One  of  the  small  branches  in  the  framework  of  a  leaf. 
Velum. -The  indusium  in  Isoetes. 
Venation.— The  manner  in  which  the  veins  are  arranged  in  the 

leaf. 
Vernation.  — The  arrangement  of  leaves  in  the  bud. 
Viviparous.  —Producing  young  upon  various  parts  of  the  plant. 
Whorl.  — A  circle  ;  as  of  leaves  on  a  stem. 
Winged. — Bordered  with  tissue,  as  the  rachis  of  some  ferns. 


Index   to   the    Common    Names, 


Bamboo,  23. 
Bird's-nest  moss,  163. 
Bog  club-moss,  114. 
Bolandei's  quillvvort,  227. 
Bottle-brush,  49,  58. 
Branched  scouring-rush,  33. 
Braun's  quillwort,  219. 
lUick-grass,  85. 
Buck-horn,  84. 
Bunch  evergreen,  loi. 

C  ALA  MITES,  6. 

Carolina  club-moss,  120. 
Cat's-tail,  49. 
Colt's-tail,  49. 
Common  club-moss,  81. 
Common  scouring-rush,  19. 
Coral  evergreen,  85. 
Corn  horsetail,  49. 
Creeping-jenny,  93. 
Creeping  selaginella,  155. 
Crowfoot,  lor. 

D.U'icH  rush,  24. 
Dwarf  scouring-rush,  38. 

Eaton's  quillwort,  236. 
Engelmann's  quillwort,  233, 


Fkstoon  ground-pine, 
Field  horsetail,  43. 
Fir  club-moss,  112. 


93- 


Fox-tail,  49,  84. 
Fox-tail  club-moss,  116. 
Frog's  fishing-poles,  24. 

Good  hick,  85,  114. 
Great  scouring-rush,  26. 
Great  water  horsetail,  53. 
Grey  moss,  143. 
Ground-cedar,  93. 
Ground-fir,  93, 
Ground-pine,  84,  88, 
Gunbright,  23. 

Heat}!  cypress,  95. 
Hemlock  club-moss,  no. 
Hog-bed,  93. 
Horse-pipes,  24. 

Interrupted  club-moss,  87. 
Ivory  horsetail,  50. 

Joint-grass,  23,  62. 
Joint-rush,  23,  49. 

Lake  quillwort,  224. 
Lamb's-tail,  85. 
Lepidodendron,  6. 
Liberty,  93. 

Mare's-tail,  49. 
Marsh  horsetail,  62. 
Matte-grass,  85. 
Meadow  pine,  49. 
Merlin's-grass,  224. 


INDEX  TO  THE  COMMON  NAMES. 


275 


Mountain  rush,  24. 
-Mud  horsetail,  53,  62. 

Nakkd  horsetail,  23. 

Orkgon  selaginella,  148. 

PADUoCK-pipes,  24,  49,  62, 

Pepperwort,  18S. 

Pill  wort,  206. 

Pine-grass,  49. 

Pine-top,  49. 

Pipes,  24. 

Polishing-rush,  23. 

Prickly  mountain  moss,  150. 

Princess  pine,  93. 

Rksurrection  moss,  161. 
Resurrection  plant,  163. 
River-bank  quillwort,  239. 
Rock  selaginella,  139. 
Running  moss,  85. 
Running  pine,  84,  93. 

Salvinia,  175. 
Savin-leaved  club-moss,  95. 
Scouring-rush,  23. 
Scrub-grass,  23. 
Shade  horsetail,  53. 
Shave -grass,  23. 
Shining  club-moss,  107. 


Shore  horsetail,  65. 
Sigillarias,  6. 
Smoke-rush,  49. 
Smoke-weed,  24. 
Smooth  scouring-rush,  30. 
Snake-grass,  49. 
Snake-moss,  85. 
Snake-rush,  24. 
Snake-weed,  24. 
Stag-horn,  84. 
Stag-horn  club-moss,  loi 
Stiff  club-moss,  86. 
Swamp  evergreen,  no. 

Tad-pipes,  49. 

Toad-pipes,  49. 

Toad-tail,  85. 

Trailing  Christmas-green,  84,  93. 

Tree  club-moss,  99. 

Tuckerman's  quillwort,  225. 

Variegated  scouring-rush,  36. 
Virgin  Mary's  furze,  114. 

Water  fern,  170,  181. 
Water  horsetail,  58. 
Water-pepper,  206. 
Winter-rush,  24. 
Wolf  s-claw,  85. 
Wood  horsetail,  53. 


Index   to   the   Scientific    Names, 


Synonyms  and  exotic  s/cc/i's  are  italicised. 


Anab.^na. 

Azolhc,  182. 

AZOLLA. 

Caroliniana,  181. 
filiculoides.  183. 
Equisetum. 
arvense,  43. 

f.  canii5estre,  48. 

f.  decumbens,  47. 

f.  diffusum,  47. 

f.  pseudosilvaticum,  47 
Ferrissi,  28. 
fluvialile,  58. 

f.  limosum,  62. 
Funstoni,  34. 
giganteum,  33. 
hiemale,  19. 

f.  intermedium,  25. 

robustum,  26. 
laevigatum,  30. 
liltorale,  65. 
Mexicannm,  33. 
palustre,  62. 
pratense,  53. 
rainosissijniiin,  2)3- 
scirpoides,  38. 
silvaticum,  53. 
telmateia,  50. 
variegatum,  36. 

Alaskan um,  38. 


ISOETKS. 

anibigua,  223. 
Bolanderi,  227. 

pygmaea,  228. 
Butleri,  252. 

inimaculata,  252. 
Canadensis,  237. 

Robbinsii,  238. 
Dodgei,  237. 
Eatoni,  236. 
echinospora,  221. 

Braunii,  220. 

Boottii,  221. 

Flettii,  222. 

maritima,  223, 

muricata,  222. 

robusta,  221. 

truncata,  222. 
Engelmanni,  233. 

Caroliniana,  235. 

fontana,  235. 

Georgiana,  235. 

gracilis,  235. 

vaiida,  236. 
flaccida,  244. 

Chapman i,  245. 

rigida,  245. 
foveolata,  241. 

plenospora,  242. 
Gravesii,  242. 


INDEX  TO  THE  SCIENTIFIC  NAMES. 


277 


ffarveyi,  226. 
heterospora,  227. 
hieroglyphica,  228. 
Howelli,  245. 

Piperi,  246. 
lacustris,  224. 

paupercula,  225. 
Macouni,  229. 
macrospora,  224. 
mar  it i ma,  223. 
nielanopoda,  250. 

Califoniica,  2^\. 

pallida,  252. 
melanospora,  246. 
minima,. 254. 
Hilda ^  246. 
Nuttallii,  252. 
Occidentalism  225. 
Orcutti,  253. 
paupercula,  225. 
Piperi^  246. 
pygmcea,  228. 
riparia,  239. 
sacchaiata,  240, 

A  me  sit,  241. 

Palmeri,  241. 

reticulata,  241. 
Tuckermani,  225. 

borealis,  226. 

heterospora,  227. 
truncata,  222, 
Underwoodii,  246. 
Lycopodium. 

adpressnm  ,118. 
alopecuroides,  117. 

adpressum,  118. 

polyclavatum,  119. 

C/iapmani,  118. 
alpinum,  94. 
annotinum,  86. 

pungens,  87. 
Carolinianum,  120. 


chamcecyparisstis,  91. 
cernuum,  lor. 
C/iapmaiii,  118. 
clavatum,  81. 

f.  monostaciiyon,  84. 
complanatum,  88. 

chamaecyparissus,' 

f.  flabelliforme,  91. 

ti'istachyon,  92. 

f.  Wibbei,  92. 
inundatum,  1 14. 

f.  lUgelovii,  116. 
lucidulum,  107. 

f.  occidentale,   in. 

porophylum,  in. 

monostaciiyon,  84. 

nikoense,  97. 

obscurum,  99. 
porophylum,  in. 
pinnatum,  119. 

sabinaefolium,  96. 

sclaginelloidcs,  151. 

selago,  1 12. 

f.  patens,  11 1, 
hicidulnm,  113. 

Sitchense,  98. 

tristachyon,  92. 
Marsilia. 

hirsuta,  200. 

macropoda,  200. 

macropns,  201. 

polycarpa,  188. 

quadrifolia,  195. 

qjiadrifoliata,  197. 

tenuifolia,  201. 

uncinata,  197. 

vestita,  199. 
PsiLOTUM. 

nudum,  127. 

triquetrum,  125. 
Salvinia. 

natans,  175. 


278 


INDEX  TO  THE  SCIENTIFIC  NAMES. 


Selaginella. 

acanthonota,  142 
apus,  155. 
arenaria,  146. 
arenicola,  144. 
Bigelovii,  146. 
bry  aides,  148. 
Caribensis,  165. 
cinerascens,  147. 
densely  142. 
Douglasii,  160. 
lepidophylla,  161. 
Ludoviciana,   158. 
viHtica,  144. 
Oregana,  148. 
Pilifera^  164. 


Pringlei,  163. 
rupestris,   139. 

acanthonota,  14: 

densa,  142. 

Fendleri,  142. 

rupincola,  142. 

Sherwoodii,  142. 

tortipila,  142. 
rupincola.,  142. 
She?'7iioodii,  142. 
spinosa,  150. 
Stnithioloides.,  1 50. 
tortipila,  142. 
Watsoni,  143. 

mutica,  144. 


RETURN     BIOLOGY  LIBRARY 

TO— »     3503  Life  Sciences  BIdg.     642 


m^ 


LOAN  PERIOD  1 


1  -MONf  H-MONOGR  APH 


ALL  BOOKS  MAY  BE  RECALLED  AFTER  7  DAYS 
Renewed  books  are  subject  to  immediate  recall 

DUE  AS  STAMPED  BELOW 


^^s^'^ 


jUN-1^9^ 


Ma^ 


^^URNEo 


2  7  \m 


Bioteof 


tm^w 


FORM  NO.  DD4 


UNIVERSITY  OF  CALIFORNIA, 
BERKELEY,  CA  94720 


UC  BERKELEY^UBR^ARIES 

i 


COBblS^m 


],![3RAR 


UNIVERSITY  OF  CAUFORNIA  UBRARY 


'1S^ 


